Stroke

Overview

Burden

No burden claims are published.

Claims and evidence

No claims are published for this condition yet.

Clinical links

Each link reports what one cited claim says about one population. "Evaluated for" means studied, not shown to work. These links do not show that anything is effective or right for you.

• Claim, not a settled fact Risk raised by: Hypertension (high blood pressure) (Associated with a higher risk of, seen from the other side)

  Applies to Recipient not specified

  • The background passages state no population. They are general statements in a guideline about sodium intake in adults and children, so the claim is not scoped to an age group or to pregnancy.
  • Not stated in the source
  • Not stated in the source
  • Not stated in the source
  • Gestational age Not reported
  • Postnatal age Not reported

  Follow-up Not applicable (background statement)
  The WHO 2012 sodium guideline calls hypertension a major risk factor for cardiovascular disease, in particular for heart attack and stroke. It also says the link between higher blood pressure and higher risk of cardiovascular disease, coronary heart disease and stroke most of all, is well established.

  Limitations. A background statement in a guideline about sodium; the fetched text gives no study data for it and does not say how much hypertension raises stroke risk. The second statement concerns blood pressure as a continuous measure, not the diagnosis of hypertension. It does not say that lowering blood pressure prevents stroke.

• Claim, not a settled fact Evaluated for this: Salt substitution (lower-sodium, potassium-containing salt) (Evaluated for, seen from the other side)

  Applies to Recipient not specified

  • People who had had a stroke, or who were 60 years of age or older and had high blood pressure, living in rural villages in China. The registry defines high blood pressure as uncontrolled: systolic 140 mmHg or more on treatment, or 160 mmHg or more without treatment. In the trial 72.6% had a history of stroke and 88.4% a history of hypertension, and the mean age was 65.4 years. No source read gives a minimum age, and the past-stroke group has no stated age floor, so the recipient is recorded as unknown rather than adult. Pregnancy is not mentioned in the sources read.
  • Rural villages in China, 600 of them. The registry names five Northern Chinese provinces and Tibet. A household phone was an entry requirement.
  • Rural China: five Northern Chinese provinces and Tibet (registry description)
  • Mixed ages with a mean of 65.4 years. Age 60 or over is required for people without a past stroke; no age floor is stated for people with one.
  • Gestational age Not reported
  • Postnatal age Not reported

  Follow-up Mean follow-up 4.74 years (abstract). The registry gives a time frame of 5 years.
  In SSaSS, in rural Chinese villages, people who had had a stroke or were 60 or older with high blood pressure had fewer strokes when their village used a lower-sodium, potassium-enriched salt substitute, with ongoing dietary advice, than when it kept using regular salt. Over a mean follow-up of 4.74 years the stroke rate was 29.14 events per 1000 person-years with the substitute and 33.65 with regular salt (rate ratio 0.86, 95% CI 0.77 to 0.96).

  Limitations. One open-label, cluster-randomized trial in rural China. The result applies to people who had had a stroke or were 60 or over with high blood pressure and met the other entry rules, such as no potassium-sparing diuretic, potassium supplement or serious kidney impairment in the household. It does not show the same effect in other groups or places. The tested package is ongoing dietary advice plus the substitute, compared with dietary advice at baseline only (registry). The abstract calls the trial open-label, while the registry records masking as DOUBLE (investigator and outcomes assessor); the two are not reconciled. The registry counts 20996 participants and the abstract 20,995; the reason is unknown. Only the abstract and the registry were read: the NEJM full text returned HTTP 403 and no open copy exists, so event counts, person-years, per-arm intervals and any correction are not recorded.

• Claim, not a settled fact Risk raised by: High sodium intake (Associated with a higher risk of, seen from the other side)

  Applies to Adult

  • Adults in the general population, with or without hypertension. The 2012 text also applies the recommendation to pregnant and lactating women; that item belongs to the maternal atlas and is outside this context. The 2012 text excludes people with illnesses or medicines that can cause low blood sodium or sudden fluid retention, and people who need physician-supervised diets, such as people with heart failure or type 1 diabetes.
  • Not stated as a care setting. The guidance covers everyday dietary sodium intake.
  • Global guidance. The cohort studies in the 2012 meta-analysis were conducted in Europe, Japan and the United States.
  • Adult; the sources set no age bounds in the passages read

  Follow-up Not applicable to the recommendation. The cohort studies in the 2012 summary followed adults for 3.8 to 22 years.
  The WHO 2012 sodium guideline reports that, in cohort studies of adults, people who ate more sodium had more strokes than people who ate the least. The pooled risk ratio was 1.24 (95% CI 1.08 to 1.43) for stroke and 1.63 (95% CI 1.27 to 2.10) for fatal stroke. WHO rated the evidence very low quality for stroke and low quality for fatal stroke. These are observational comparisons of higher and lower intake groups.

  Limitations. Observational cohort data with very low to low quality ratings from WHO. Groups were compared on sodium intake, not on a change in intake, and the guideline notes that some cohort studies found no link, an inverse link (higher intake with lower risk) or a J-shaped curve. Intake ranges differed widely between studies, and the lowest-intake groups in some studies ate as much as 4 g of sodium a day, so the comparison is not intake above against below the WHO limit of 2 g. Nothing here shows that cutting sodium prevents strokes; the SSaSS claim concerns a different intervention.

Record details

Record id

core:stroke

Content hash

0ce1f0f5527ece7b16d91bcd88df1e4dfe54b96caac0cb683b9a58b530e9a215