HDL cholesterol after quitting: a mean rise, not a recovered lipid panel

01

HDL-C is not LDL-C, particle count or an event

HDL-C measures cholesterol carried in high-density lipoproteins. It is distinct from LDL-C, triglycerides, total cholesterol and the number of HDL particles. The label ‘good cholesterol’ is shorthand, not a declaration that the whole lipid profile or cardiovascular risk is good. In this study, LDL-related changes were not statistically clear, and triglyceride findings were not clear after correction for multiple comparisons. This does not prove that those measures can never change.

[1][3][4]

02

A randomized treatment study, but not randomized successful quitting

The Wisconsin study recruited 1,504 motivated adult smokers in 2005–2007. Treatments were randomized; whether a participant successfully stopped was not. Only 923 returned at one year. The visit-abstinent group reported no smoking in the previous seven days, supported by exhaled carbon monoxide indicating recent exposure. That does not verify continuous abstinence throughout the year.

The comparison table keeps the simultaneous weight rise visible: a favourable average HDL-C change and weight gain can coexist. Models considered weight and several baseline factors, but later changes in alcohol use and activity were unavailable. About 39% missed the visit, the sample was mainly white, and there was no never-smoker control. The study cannot show that every quitter returned to a never-smoker level.

[1]

03

Why the pooled estimate is not a three-week target

A 2013 review identified 45 studies; its numerical analysis used 94 change estimates from 42 studies, not 94 independent trials. Its inverse-variance-weighted mean rise was 0.060 mmol/L (95% confidence interval 0.044–0.075), versus 0.107 (0.085–0.128) without weighting. Different study lengths and sizes affected these summaries, and missing variability often had to be estimated. Some quit times were inferred from interval midpoints. The review included the Wisconsin study, so it is not an independent replication of it. It also disclosed tobacco-company funding and tobacco-industry consulting relationships. These limitations rule out using the pooled averages as a personal improvement amount or deadline.

[1][2]

04

An unchanged result does not grade your quit attempt

The one-year analysis measured lipids, not subsequent heart attacks or strokes. It cannot convert a rise of a few mg/dL into your event-risk reduction. Conversely, an HDL-C value that does not rise cannot establish that stopping smoking was useless. Personal test interpretation and cardiovascular decisions require a qualified clinician considering the whole situation; this page sets no target, test schedule, diet, exercise or medicine plan.

For separate smoking support in England, NHS Better Health points to local Stop Smoking Services; elsewhere, ask your local health service about available help. A research average is not a condition you must meet before asking for support.

[1][2][3][4][5]

05

What to keep in mind

• Mean HDL-C, other lipids, weight and actual events are separate outcomes.
• One-year visit abstinence is not verified continuous abstinence for a year.