The number of smokers needed to screen and treat in a smoking cessation programme

Smoking cessation is an important factor in reducing cardiovascular mortality, but considerable effort is needed to successfully persuade patients to quit smoking. We studied the efficiency of the Minimal Intervention Strategy (C-MIS) in addition to nicotine replacement therapy (NRT) for smoking cessation in cardiovascular outpatients in relation to the outcome of mortality.

Prospective cohort data studying the C-MIS in three outpatient clinics: cardiology, vascular surgery and vascular medicine.

Two thousand, two hundred and seventy-five consecutive patients attending the clinics for first or routine follow-up visits were screened for atherosclerosis and smoking. The efficiency of the C-MIS was expressed as the number of smokers needed to screen and needed to treat in relation to the number of deaths prevented over a 5-year period. Mortality estimates were derived from the literature.

One thousand, four hundred and thirty-one patients were screened at first-time follow-up visits and 1294 at routine follow-up visits. With a rate of effectiveness of 4.3% for the C-MIS, the number needed to treat was 240 (min-max: 64-infinity) to prevent one death. The corresponding number needed to screen was 687 (min-max: 141-infinity) in the cardiology clinic, 574 (min-max: 134-infinity) in the vascular surgery clinic and 444 (min-max: 90-infinity) in the vascular medicine clinic. Within 5 years, 10 (min-max: 0-58) deaths could be prevented in all three clinics together. With the effectiveness of the C-MIS for first-time and routine follow-up attendees, only six (min-max: 0-36) and zero (min-max: 0-25) deaths could be prevented, respectively.

In terms of the efficiency of the C-MIS in addition to nicotine replacement therapy, there is some benefit for first-time attendees and no benefit for routine follow-up attendees in preventing death.