[Federal Register Volume 82, Number 42 (Monday, March 6, 2017)]
[Notices]
[Pages 12605-12610]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-04193]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Agency for Healthcare Research and Quality


Supplemental Evidence and Data Request on Effects of Dietary 
Sodium and Potassium Intake on Chronic Disease Outcomes and Related 
Risk Factors

AGENCY: Agency for Healthcare Research and Quality (AHRQ), HHS.

ACTION: Request for Supplemental Evidence and Data Submissions.

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SUMMARY: The Agency for Healthcare Research and Quality (AHRQ) is 
seeking scientific information submissions from the public. Scientific 
information is being solicited to inform our review of Effects of 
Dietary Sodium and Potassium Intake on Chronic Disease Outcomes and 
Related Risk Factors, which is currently being conducted by the AHRQ's 
Evidence-based Practice Centers (EPC) Program. Access to published and 
unpublished pertinent scientific information will improve the quality 
of this review. AHRQ is conducting this systematic review pursuant to 
Section 902(a) of the Public Health Service Act, 42 U.S.C. 299a(a).

DATES: Submission Deadline on or before April 5, 2017.

ADDRESSES: Email submissions: src.org">SEADS@epc-src.org.
    Print submissions: Mailing Address: Portland VA Research 
Foundation, Scientific Resource Center, ATTN: Scientific Information 
Packet Coordinator, P.O. Box 69539, Portland, OR 97239.
    Shipping Address (FedEx, UPS, etc.): Portland VA Research 
Foundation, Scientific Resource Center, ATTN: Scientific Information 
Packet Coordinator, 3710 SW U.S. Veterans Hospital Road, Mail Code: R&D 
71, Portland, OR 97239.

FOR FURTHER INFORMATION CONTACT: Ryan McKenna, Telephone: 503-220-8262 
ext. 51723 or Email: src.org">SEADS@epc-src.org.

SUPPLEMENTARY INFORMATION: The Agency for Healthcare Research and 
Quality has commissioned the Evidence-based Practice Centers (EPC) 
Program to complete a review of the evidence for Effects of Dietary 
Sodium and Potassium Intake on Chronic Disease Outcomes and Related 
Risk Factors.
    The EPC Program is dedicated to identifying as many studies as 
possible that are relevant to the questions for each of its reviews. In 
order to do so, we are supplementing the usual manual and electronic 
database searches of the literature by requesting information from the 
public (e.g., details of studies conducted). We are looking for studies 
that report on Effects of Dietary Sodium and Potassium Intake on 
Chronic Disease Outcomes and Related Risk Factors, including those that 
describe adverse events. The entire research protocol, including the 
key questions, is also available online at: https://www.effectivehealthcare.AHRQ.gov/index.cfm/search-for-guides-reviews-and-reports/?pageaction=displayproduct&productid=2428.
    This is to notify the public that the EPC Program would find the 
following information on Effects of Dietary Sodium and Potassium Intake 
on Chronic Disease Outcomes and Related Risk Factors helpful:
    [ssquf] A list of completed studies that your organization has 
sponsored for this indication. In the list, please indicate whether 
results are available on ClinicalTrials.gov along with the 
ClinicalTrials.gov trial number.
    [ssquf] For completed studies that do not have results on 
ClinicalTrials.gov, please provide a summary, including the following 
elements: Study number; study period; design, methodology; indication 
and diagnosis; proper use instructions; inclusion and exclusion 
criteria; primary and secondary outcomes; baseline characteristics; 
number of patients screened, eligible, enrolled, lost to follow up, 
withdrawn, and analyzed; as well as effectiveness and efficacy, and 
safety results.
    [ssquf] A list of ongoing studies that your organization has 
sponsored for this

[[Page 12606]]

indication. In the list, please provide the ClinicalTrials.gov trial 
number or, if the trial is not registered, the protocol for the study 
including a study number, the study period, design, methodology, 
indication and diagnosis, proper use instructions, inclusion and 
exclusion criteria, and primary and secondary outcomes.
    [ssquf] Description of whether the above studies constitute ALL 
Phase II and above clinical trials sponsored by your organization for 
this indication and an index outlining the relevant information in each 
submitted file.
    Your contribution will be very beneficial to the EPC Program. The 
contents of all submissions will be made available to the public upon 
request. Materials submitted must be publicly available or able to be 
made public. Materials that are considered confidential; marketing 
materials; study types not included in the review; or information on 
indications not included in the review cannot be used by the EPC 
Program. This is a voluntary request for information, and all costs for 
complying with this request must be borne by the submitter.
    The draft of this review will be posted on AHRQ's EPC Program Web 
site and available for public comment for a period of 4 weeks. If you 
would like to be notified when the draft is posted, please sign up for 
the email list at: https://www.effectivehealthcare.ahrq.gov/index.cfm/join-the-email-list1/.
    The systematic review will answer the following questions. This 
information is provided as background. AHRQ is not requesting that the 
public provide answers to these questions.

The Key Questions

Sodium

    1. Among adults and children of all age groups (including both 
sexes and pregnant and lactating women), what is the effect (benefits 
and harms) of interventions to reduce dietary sodium intake on blood 
pressure at the time of the study and in later life?
    I. Do other minerals (e.g., potassium, calcium, magnesium) modify 
the effect of sodium?
    II. Among subpopulations defined by sex, race/ethnicity, age 
(children, adolescents, young adults, older adults, elderly), and for 
women (pregnancy and lactation).
    III. Among subpopulations defined by hypertension, diabetes, and 
obesity health status.
    2. Among adults and children, what is the association between 
dietary sodium intake and blood pressure?
    I. Among subpopulations defined by sex, race/ethnicity and age 
(children, adolescents, young adults, older adults, elderly).
    II. Among subpopulations defined by hypertension, diabetes, and 
obesity health status.
    3. Among adults, what is the effect (benefits and harms) of 
interventions to reduce dietary sodium intake on cardiovascular disease 
(CVD) and kidney disease morbidity and mortality and on total 
mortality?
    I. Do other minerals (e.g., potassium, calcium, magnesium) modify 
the effect of sodium?
    II. Among subpopulations defined by sex, race/ethnicity, age 
(adults, older adults, elderly), and for women (pregnancy and 
lactation).
    III. Among subpopulations defined by hypertension, diabetes, 
obesity and renal health status.
    4. Among adults, what is the association between dietary sodium 
intake and CVD, coronary heart disease (CHD), stroke and kidney disease 
morbidity and mortality and between dietary sodium intake and total 
mortality?
    I. Do other minerals (e.g., potassium, calcium, magnesium) modify 
the association with sodium?
    II. Among subpopulations defined by sex, race/ethnicity, age 
(adults, older adults, elderly), and for women (pregnancy and 
lactation).
    III. Among subpopulations defined by hypertension, diabetes, 
obesity and renal health status.

Potassium

    5. Among children and adults, what is the effect of interventions 
to increase potassium intake on blood pressure and kidney stone 
formation?
    I. Do other minerals (e.g., sodium, calcium, magnesium) modify the 
effect of potassium?
    II. Among subpopulations defined by sex, race/ethnicity, age 
(children, adolescents, young adults, older adults, elderly), and for 
women (pregnancy and lactation).
    III. Among subpopulations defined by hypertension, diabetes, 
obesity and renal health status.
    6. Among children and adults, what is the association between 
potassium intake and blood pressure and kidney stone formation?
    I. Among subpopulations defined by sex, race/ethnicity, and age 
(children, adolescents, young adults, older adults, elderly).
    II. Among subpopulations defined by hypertension, diabetes, and 
obesity health status.
    7. Among adults, what is the effect of interventions aimed at 
increasing potassium intake on CVD, and kidney disease morbidity and 
mortality, and total mortality?
    I. Do other minerals modify the effect of potassium (e.g., sodium, 
calcium, magnesium)?
    II. Among subpopulations defined by sex, race/ethnicity, age (young 
adults, older adults, elderly), and for women (pregnancy and 
lactation).
    III. Among subpopulations defined by hypertension, diabetes, 
obesity and renal health status.
    8. Among adults, what is the association between dietary potassium 
intake and CVD, CHD, stroke and kidney disease morbidity and mortality 
and between dietary potassium and total mortality?
    I. Do other minerals (e.g., sodium, calcium, magnesium) modify the 
association with potassium?
    II. Among subpopulations defined by sex, race/ethnicity, age (young 
adults, older adults, elderly), and for women (pregnancy and 
lactation).
    III. Among subpopulations defined by hypertension, diabetes, and 
obesity health status.

PICOTS (Populations, Interventions, Comparators, Outcomes, Timing, 
Settings)

Key Question 1
I. Population
    A. Studies in human participants will be eligible for inclusion in 
the review, with the exception of studies exclusively reporting on 
patients with end stage renal disease, heart failure, HIV, or cancer.
II. Interventions
    A. Studies evaluating interventions to reduce dietary sodium intake 
that specify the oral consumption from food or supplements of 
quantified amounts of sodium and sodium chloride (salt) or sodium-to-
potassium ratio will be eligible, with the exception of trial arms in 
which participants demonstrate a weight change of +/- 3% or more. 
Interventions simultaneously addressing sodium and potassium intake 
that document sodium/potassium ratio are eligible; all other 
multicomponent interventions in which the effect of sodium reduction 
cannot be disaggregated from other intervention components will be 
excluded.
III. Comparators
    A. Studies comparing interventions to placebo or control diets will 
be eligible. Studies comparing an experimental diet to usual diet, 
studies comparing levels of sodium intake, or studies that alter 
sodium/potassium ratio in other ways

[[Page 12607]]

will be included if they control for other nutrient levels.
IV. Outcomes
    A. Studies reporting on blood pressure outcomes (e.g., systolic 
blood pressure, diastolic blood pressure, rate of hypertensive/non-
hypertensive participants, incident hypertension, percent of 
participants at blood pressure goal, and change in blood pressure) will 
be eligible.
V. Timing
    A. Studies reporting on an intervention period of at least four 
weeks will be eligible.
VI. Setting
    A. Studies in outpatient settings will be eligible.
VII. Study Design
    A. Parallel RCTs and cross-over RCTs with a washout period of two 
weeks or more will be eligible.
Key Question 2
I. Population
    A. Studies in community-dwelling (non-institutionalized) human 
participants will be eligible for inclusion in the review with the 
exception of studies exclusively reporting on patients with pre-
existing conditions specific to the clinical outcome of interest, as 
well as studies exclusively reporting on patients with end stage renal 
disease, heart failure, HIV, or cancer.
II. Exposure
    A. Studies that measure the intake (oral consumption from food or 
supplements of quantified amounts of sodium and sodium chloride [salt] 
or sodium-to-potassium ratio) with validated measures or that use 
biomarker values to assess sodium level (at least one 24-hour urinary 
analysis with or without reported quality control measure, chemical 
analysis of diet with intervention/exposure adherence measure, 
composition of salt substitute with intervention/exposure adherence 
measure, and food diaries with reported validation [adherence check, 
electronic prompts]) will be eligible. Observational studies that 
report a weight change of +/- 3% or more (in any exposure group) among 
adults; multicomponent studies that do not properly control for 
confounders; and studies relying only on serum sodium levels, 
composition of salt substitute without intervention/exposure adherence 
measure, food diaries without reported validation, use of a published 
food frequency questionnaire, or partial or spot urine without reported 
prediction equation will be excluded.
III. Comparator
    A. Studies comparing groups with different documented sodium intake 
or biomarker values for sodium will be eligible. Studies where 
differences in sodium intake or values are confounded with alteration 
of other nutrient levels will be excluded.
IV. Outcomes
    A. Studies reporting on blood pressure outcomes (e.g., systolic 
blood pressure, diastolic blood pressure, rate of hypertensive/non-
hypertensive participants, incident hypertension, percent of 
participants at blood pressure goal, change in blood pressure) will be 
eligible. Studies that do not report baseline blood pressure status 
will be excluded.
V. Timing
    A. Studies reporting on an intervention period of at least four 
weeks will be eligible.
VI. Setting
    A. Studies in community-dwelling participants will be eligible.
VII. Study Design
    A. Prospective cohort studies and nested case-control studies, 
where at least two groups are compared based on measured sodium intake 
or biomarker values will be eligible. Retrospective studies, case 
series, cross-sectional studies or surveys, and case reports will be 
excluded.
Key Question 3
I. Population
    A. Studies in human adults will be eligible for inclusion in the 
review. Studies exclusively reporting on patients with end stage renal 
disease, heart failure, HIV, or cancer will be excluded.
II. Intervention
    A. Studies evaluating interventions to reduce dietary sodium intake 
that specify the oral consumption from food or supplements of 
quantified amounts of sodium and sodium chloride (salt) or sodium-to-
potassium ratio will be eligible. Studies with trial arms in which 
participants demonstrate a weight change of +/- 3% or more will be 
excluded. Interventions simultaneously addressing sodium and potassium 
intake with documents sodium/potassium ratio are eligible. All other 
multicomponent interventions in which the effect of sodium reduction 
cannot be disaggregated from other intervention components will be 
excluded.
III. Comparators
    A. Studies comparing interventions to placebo or control diets will 
be eligible. Studies comparing an experimental diet to usual diet, 
studies comparing levels of sodium intake, or studies that alter 
sodium/potassium ratio in other ways will be included if they control 
for other nutrient levels.
IV. Outcomes
    A. Studies reporting on mortality (all-cause, CVD, CHD, or renal); 
cardiovascular disease morbidity, including acute coronary syndrome 
(unstable angina and myocardial infarction), stroke, myocardial 
infarction (ST-segment elevation myocardial infarction [STEMI] and non-
ST elevation myocardial infarction [NSTEMI]), requiring coronary 
revascularization procedures (angioplasty, coronary stent placement, 
coronary artery bypass), other atherosclerotic revascularization 
procedures (carotid endarterectomy), left ventricular hypertrophy, 
hospitalization for heart failure, hospitalization for any cause of 
coronary heart disease or cardiovascular disease, or combined CVD 
morbidity and mortality; or reporting on renal function intermediary 
and clinical outcomes including creatinine clearance (CrCl), serum 
creatinine (SCr), glomerular filtration rate (GFR), end stage renal 
disease, chronic kidney disease (CKD), albuminuria or proteinuria 
(including urine albumin-to-creatinine ratio, urine albumin dipstick 
level, urine protein-to-creatinine ratio, albumin excretion rate), 
kidney stone incidence, or acute kidney injury will be eligible.
V. Timing
    A. Only interventions of two years or longer will be included for 
kidney disease outcomes; only interventions of three months or longer 
will be included for cardiovascular disease outcomes; all other studies 
need to report on an intervention period of at least four weeks to be 
eligible.
VI. Setting
    A. Studies in outpatient settings will be eligible.
VII. Study Design
    A. Parallel RCTs and cross-over RCTs with a washout period of two 
weeks or more will be eligible.

[[Page 12608]]

Key Question 4
I. Population
    A. Studies in community-dwelling (non-institutionalized) adults 
will be eligible for inclusion in the review with the exception of 
studies exclusively reporting on patients with pre-existing conditions 
specific to the clinical outcomes of interest, as well as studies 
exclusively reporting on patients with end stage renal disease, heart 
failure, HIV, or cancer.
II. Exposure
    A. Studies that measure the intake (oral consumption from food or 
supplements of quantified amounts of sodium and sodium chloride [salt] 
or sodium-to-potassium ratio) with validated measures or use biomarker 
values to assess sodium level (at least one 24-hour urinary analysis 
with or without reported quality control measure, chemical analysis of 
diet with intervention/exposure adherence measure, composition of salt 
substitute with intervention/exposure adherence measure, and food 
diaries with reported validation [adherence check, electronic prompts]) 
will be eligible. Observational studies that report a weight change of 
+/- 3% or more (in any exposure group) among adults; multicomponent 
studies that do not properly control for confounders; and studies 
relying only on serum sodium levels, composition of salt substitute 
without intervention/exposure adherence measure, food diaries without 
reported validation, use of a published food frequency questionnaire, 
or partial or spot urine without reported prediction equation will be 
excluded.
III. Comparator
    A. Studies comparing groups with different documented sodium intake 
or biomarker values for sodium will be eligible. Studies where 
differences in sodium intake or values are confounded with alteration 
of other nutrient levels will be excluded.
IV. Outcomes
    A. Studies reporting on mortality (all-cause, CVD, CHD, or renal); 
cardiovascular mortality; cardiovascular disease morbidity, including 
coronary heart disease (CHD), acute coronary syndrome (unstable angina 
and myocardial infarction), stroke, myocardial infarction (ST-segment 
elevation myocardial infarction [STEMI] and non-ST elevation myocardial 
infarction [NSTEMI]), requiring coronary revascularization procedures 
(angioplasty, coronary stent placement, coronary artery bypass), other 
atherosclerotic revascularization procedures (carotid endarterectomy), 
left ventricular hypertrophy, hospitalization for heart failure, or 
hospitalization for any cause of coronary heart disease or 
cardiovascular disease, or combined CVD morbidity and mortality; or 
reporting on renal function intermediary and clinical outcomes 
including creatinine clearance (CrCl), serum creatinine (SCr), 
glomerular filtration rate (GFR), end stage renal disease, chronic 
kidney disease (CKD), albuminuria/proteinuria (including, urine 
albumin-to-creatinine ratio, urine albumin dipstick level, urine 
protein-to-creatinine ratio, albumin excretion rate), acute kidney 
injury will be eligible. Studies that do not report baseline data for 
the outcomes of interest will be excluded.
V. Timing
    A. Studies reporting exclusively on kidney disease outcomes need to 
report follow up periods of at least two years, studies reporting 
exclusively on cardiovascular disease outcomes or stroke need to report 
on follow up periods of at least 12 months duration; studies reporting 
on other outcomes need to evaluate exposure lasting at least four weeks 
to be eligible.
VI. Setting
    A. Studies in community-dwelling participants will be eligible.
VII. Study Design
    A. Prospective cohort studies and nested case-control studies, 
where at least two groups are compared based on measured sodium intake 
or biomarker values will be eligible. Retrospective studies, case 
series, cross-sectional studies or surveys, and case reports will be 
excluded.
Key Question 5
I. Population
    A. Studies in human participants will be eligible for inclusion in 
the review; studies exclusively reporting on patients with end stage 
renal disease, heart failure, HIV, or cancer will be excluded.
II. Interventions
    A. Studies evaluating interventions to increase dietary potassium 
intake that specify the oral consumption from food or supplements of 
quantified amounts of potassium, potassium supplements, salt 
substitutes such as potassium chloride, or sodium-to-potassium ratio 
will be eligible, with the exception of trial arms in which 
participants demonstrate a weight change of +/- 3% or more among 
adults. Interventions simultaneously addressing sodium and potassium 
intake with documents sodium/potassium ratio are eligible; all other 
multicomponent interventions in which the effect of sodium reduction 
cannot be disaggregated from other intervention components will be 
excluded.
III. Comparators
    A. Studies comparing interventions to placebo or control diets will 
be eligible. Studies comparing an experimental diet to usual diet, 
studies comparing levels of potassium intake, or studies that alter 
sodium/potassium ratio in other ways will be included if they control 
for other nutrient levels.
IV. Outcomes
    A. Studies reporting on blood pressure outcomes (e.g., systolic 
blood pressure, diastolic blood pressure, rate of hypertensive/non-
hypertensive participants, hypertension incidence, percent of 
participants at blood pressure goal, change in blood pressure) and 
incident kidney stones or kidney stone regrowth will be eligible.
V. Timing
    A. Studies reporting exclusively on kidney stone formation need to 
report on an intervention period of two years; all other studies need 
to report on an intervention period of at least four weeks to be 
eligible.
VI. Setting
    A. Studies in outpatient settings will be eligible.
VII. Study Design
    A. Parallel RCTs and cross-over RCTs with a washout period of two 
weeks or more will be eligible.
Key Question 6
I. Population
    A. Studies in community-dwelling (non-institutionalized) human 
participants will be eligible for inclusion in the review; studies 
reporting exclusively on patients with pre-existing conditions specific 
to the clinical outcomes of interest, as well as studies exclusively 
reporting on patients with end stage renal disease, heart failure, HIV, 
or cancer will be excluded.
II. Exposure
    A. Studies that measure intake (oral consumption from food or 
supplements of quantified amounts of potassium, potassium supplements, 
salt substitutes such as potassium chloride, or sodium-to-potassium 
ratio) with validated measures or use biomarkers values to assess 
potassium level (at least one 24-hour urinary analysis with or without

[[Page 12609]]

reported quality control measure, chemical analysis of diet with 
intervention/exposure adherence measure, composition of potassium 
supplement with intervention/exposure adherence measure, use of a 
published food frequency questionnaire, and food diaries) will be 
eligible. Observational studies that report a weight change of +/- 3% 
or more (in any exposure group) among adults; multicomponent studies 
that do not properly control for confounders; and studies measuring 
potassium intake by reporting chemical analysis of diet without 
intervention/exposure adherence measures, composition of potassium 
supplement without intervention/exposure measure, or serum potassium 
will be excluded.
III. Comparator
    A. Studies comparing groups with different documented potassium 
intake, serum potassium levels, or urinary potassium excretion will be 
eligible. Studies where differences in potassium intake or values are 
confounded with alteration of other nutrient levels will be excluded.
IV. Outcomes
    A. Studies reporting on blood pressure outcomes (e.g., systolic 
blood pressure, diastolic blood pressure, rate of hypertensive/non-
hypertensive participants, hypertension incidence, percent of 
participants at blood pressure goal, change in blood pressure), and 
kidney stone incident or kidney stone regrowth will be eligible. 
Studies that do not report baseline blood pressure status and the 
presence or absence of kidney stones will be excluded.
V. Timing
    A. Studies exclusively reporting on kidney stone formation need to 
follow participants for at least five years; all other studies need to 
report on exposure of at least four weeks to be eligible.
VI. Setting
    A. Studies in community-dwelling participants will be eligible.
VII. Study Design
    A. Prospective cohort studies and nested case-control studies, 
where at least two groups are compared based on measured potassium 
intake or biomarker values will be eligible. Retrospective studies, 
case series, cross-sectional studies or surveys, and case reports will 
be excluded.
Key Question 7
I. Population
    A. Studies in adults will be eligible for inclusion in the review; 
studies reporting exclusively on patients with heart failure, end stage 
renal disease, HIV, or cancer will be excluded.
II. Interventions
    A. Studies evaluating interventions to increase dietary potassium 
intake that specify the oral consumption from food or supplements of 
quantified amounts of potassium, potassium supplements, salt 
substitutes such as potassium chloride, or sodium-to-potassium ratio 
will be eligible, with the exception of trial arms in which 
participants demonstrate a weight change of +/- 3% or more. 
Interventions simultaneously addressing sodium and potassium intake 
with documents sodium/potassium ratio are eligible; all other 
multicomponent interventions in which the effect of sodium reduction 
cannot be disaggregated from other intervention components will be 
excluded.
III. Comparators
    A. Studies comparing interventions to placebo or control diets will 
be eligible. Studies comparing an experimental diet to usual diet, 
studies comparing levels of potassium intake, or studies that alter 
sodium/potassium ratio in other ways will be included if they control 
for other nutrient levels.
IV. Outcomes
    A. Studies reporting on mortality (all-cause, CVD, CHD, or renal); 
cardiovascular disease morbidity, including acute coronary syndrome 
(unstable angina and myocardial infarction), stroke, myocardial 
infarction (ST-segment elevation myocardial infarction [STEMI] and non-
ST elevation myocardial infarction [NSTEMI]), requiring coronary 
revascularization procedures (angioplasty, coronary stent placement, 
coronary artery bypass), other atherosclerotic revascularization 
procedures (carotid endarterectomy), left ventricular hypertrophy, 
hospitalization for heart failure, or hospitalization for any cause of 
coronary heart disease or cardiovascular disease, or combined CVD 
morbidity and mortality; or reporting on renal function intermediary 
and clinical outcomes including creatinine clearance (CrCl), serum 
creatinine (SCr), glomerular filtration rate (GFR), end stage renal 
disease, chronic kidney disease (CKD), albuminuria or proteinuria 
(including urine albumin-to-creatinine ratio, urine albumin dipstick 
level, urine protein-to-creatinine ratio, albumin excretion rate), 
kidney stone incidence, or acute kidney injury will be eligible.
V. Timing
    A. Studies reporting exclusively on kidney disease outcomes need to 
report on an intervention period of two years, studies reporting on 
cardiovascular disease or stroke need to report on an intervention 
period of three months; all other studies need to report on an 
intervention period of at least four weeks to be eligible.
VI. Setting
    A. Studies in outpatient settings will be eligible.
VII. Study Design
    A. Parallel RCTs and cross-over RCTs with a washout period of two 
weeks or more will be eligible.
Key Question 8
I. Population
    A. Studies in community-dwelling (non-institutionalized) adults 
will be eligible for inclusion in the review with the exception of 
studies exclusively reporting on patients with pre-existing conditions 
specific to the clinical outcomes of interest, as well as studies 
exclusively reporting on patients with end stage renal disease, heart 
failure, HIV, or cancer.
II. Exposure
    A. Studies that measure intake (oral consumption from food or 
supplements of quantified amounts of potassium, potassium supplements, 
salt substitutes such as potassium chloride, or sodium-to-potassium 
ratio) with validated measures or use biomarkers values to assess 
potassium level (at least one 24-hour urinary analysis with or without 
reported quality control measure, chemical analysis of diet with 
intervention/exposure adherence measure, composition of potassium 
supplement with intervention/exposure adherence measure, use of a 
published food frequency questionnaire, and food diaries) will be 
eligible. Observational studies that report a weight change of +/- 3% 
or more (in any exposure group) among adults; multicomponent studies 
that do not properly control for confounders; and studies measuring 
potassium intake by reporting chemical analysis of diet without 
intervention/exposure adherence measures, composition of potassium 
supplement without intervention/exposure measure, or serum potassium 
will be excluded.
III. Comparator
    A. Studies comparing groups with different documented potassium 
intake, serum potassium levels, or urinary potassium excretion will be 
eligible.

[[Page 12610]]

Studies where differences in potassium intake or values are confounded 
with alteration of other nutrient levels will be excluded.
IV. Outcomes
    A. Studies reporting on mortality (all-cause, CVD, CHD, or renal); 
cardiovascular disease morbidity, including coronary heart disease 
(CHD), acute coronary syndrome (unstable angina and myocardial 
infarction), stroke, myocardial infarction (ST-segment elevation 
myocardial infarction [STEMI] and non-ST elevation myocardial 
infarction [NSTEMI]), requiring coronary revascularization procedures 
(angioplasty, coronary stent placement, coronary artery bypass), other 
atherosclerotic revascularization procedures (carotid endarterectomy), 
left ventricular hypertrophy, hospitalization for heart failure, or 
hospitalization for any cause of coronary heart disease or 
cardiovascular disease, or combined CVD morbidity and mortality; or 
reporting on renal function intermediary and clinical outcomes 
including creatinine clearance (CrCl), serum creatinine (SCr), 
glomerular filtration rate (GFR), end stage renal disease, chronic 
kidney disease (CKD), albuminuria/proteinuria (including urine albumin-
to-creatinine ratio, urine albumin dipstick level, urine protein-to-
creatinine ratio, albumin excretion rate), kidney stone incidence, or 
acute kidney injury will be eligible. Studies that do not report 
baseline data on the outcomes of interest will be excluded.
V. Timing
    A. Studies reporting exclusively on kidney stone formation need to 
follow participants for at least five years, studies reporting 
exclusively on kidney disease need to follow participants for at least 
two years, studies reporting exclusively on cardiovascular disease or 
stroke need to follow patients for at least 12 months; all other 
studies need to report on an exposure period of at least four weeks to 
be eligible.
VI. Setting
    A. Studies in community-dwelling participants will be eligible.
VII. Study Design
    A. Prospective cohort studies and nested case-control studies, 
where at least two groups are compared based on measured potassium 
intake or biomarker values will be eligible. Retrospective studies, 
case series, cross-sectional studies or surveys, and case reports will 
be excluded.

Sharon B. Arnold,
Acting AHRQ Director.
[FR Doc. 2017-04193 Filed 3-3-17; 8:45 am]
BILLING CODE 4160-90-P