Lack of an association or an inverse association between low-density-lipoprotein cholesterol and mortality in the elderly: a systematic review.
Level 3 - non-randomized controlled study
Systematic review of observational cohort studies
PubMed 27292972 · doi:10.1136/bmjopen-2015-010401
What was done
Authors conducted a systematic review searching PubMed for cohort studies examining low-density lipoprotein cholesterol (LDL-C) as a risk factor for all-cause and/or cardiovascular (CV) mortality in community-dwelling adults aged 60 years and older.
What was found
The review identified 19 cohort studies covering 30 distinct cohorts and 68,094 individuals. All-cause mortality was assessed in 28 cohorts and CV mortality in 9 cohorts. An inverse association between LDL-C and all-cause mortality was present in 16 cohorts (statistically significant in 14), representing 92% of participants assessed for this outcome; the remaining cohorts found no association. For CV mortality, 2 cohorts reported significantly higher mortality in the lowest LDL-C quartile, whereas 7 cohorts found no association. Pooled effect sizes and confidence intervals were not reported in the abstract.
Why it matters
These findings challenge the assumption that elevated LDL-C consistently increases mortality risk across all age groups, raising questions about guidelines recommending routine pharmacological LDL-lowering in elderly populations.
Limits
The underlying evidence is entirely observational, precluding causal inference. The abstract notes only a PubMed search (omitting other databases) and provides qualitative cohort counts rather than pooled meta-analytic risk estimates. Observational studies in elderly populations are also prone to reverse causation and residual confounding, such as terminal illness, frailty, or malnutrition lowering lipid levels prior to death, as well as unmeasured statin use.
Cited by
- supports A 2016 systematic review of observational cohort studies in people over age 60 found an inverse association between LDL cholesterol and all-cause mortality.
- supports A 2016 systematic review of observational cohort studies found no association between LDL cholesterol levels and cardiovascular disease in individuals aged 60 and older.