Does quitting smoking reduce recurrence after a primary spontaneous pneumothorax?

01

‘Primary’ does not mean the lung cannot collapse again

A pneumothorax involves air in the space around the lung, which can cause it to collapse. Primary spontaneous pneumothorax occurs without a known underlying lung disease or a traumatic cause. It is different from a secondary pneumothorax associated with an existing lung condition. Primary is a category, not proof that no lung changes exist or that recurrence is impossible.

Walker and colleagues' overall recurrence pool mainly concerned adults with PSP managed without surgery or pleurodesis, including observation, aspiration or chest drainage. Eligibility allowed studies with adolescents aged 11 or older if they were fewer than a quarter of participants. These are inclusion details, not treatment choices for a reader; the results cannot simply be transferred to secondary, traumatic or surgically treated pneumothorax.

[1][2][3]

02

Why 32.1% × 0.26 is not your new risk

Across 29 studies with 13,548 people, the pooled overall recurrence estimate was 32.1% (95% confidence interval 27.0–37.2); 12 studies supplied the one-year estimate of 29.0% (20.9–37.0). Different follow-up periods and study populations matter. The reported I² of 94% shows substantial variation in recurrence estimates between studies; it does not say that quitting fails in 94% of people.

The cessation subsection pooled just two observational studies, finding an odds ratio (OR) of 0.26 (0.10–0.63). Odds mean the probability of recurrence divided by the probability of no recurrence. This OR compares those odds between stopping and continuing groups; it is not a 26% personal recurrence probability or automatically a 74% reduction in absolute risk.

Multiplying the overall 32.1% by 0.26 mixes a broad recurrence average with a different, much smaller comparison and treats odds as probabilities. There is no common personal baseline in those two numbers. Stopping was not randomly assigned, and self-reported smoking, management differences and study bias limit certainty about the size of the association. The authors also noted that, although surgery and pleurodesis cases were excluded from the overall recurrence pool, these cases could not always be excluded from subgroup analyses, potentially confounding those results. The smaller cessation comparison therefore must not be assumed to have the same entirely non-operative scope.

[1]

03

The useful next question is about follow-up, not permission

Ask the respiratory team how cessation support fits alongside follow-up after the pneumothorax. A lower group recurrence estimate is not clearance to fly, dive or resume a particular activity, and does not choose a procedure. Those decisions need the treating specialist's assessment. New physical concerns should be discussed with medical professionals, not dismissed because of a group OR.

In England, NHS local stop-smoking services provide a separate support route; confirm access where you live. A practical question is: ‘Does this number describe recurrence after my type of pneumothorax and care, or a different group?’ No scan, smoking history or quit date needs to be submitted here.

[2][3][4]

04

What to keep in mind

• The quitting association came from two studies, not all 29.
• An odds ratio cannot be multiplied by the overall recurrence average.
• Cessation support does not replace follow-up or specialist clearance.