Table 4

Median weight change, BMI change and annual weight change between admission and follow-up by tobacco use and substance misuse (drug and alcohol)

All, n (%)Median weight change, kg (95% CI)P valueMedian BMI change, kg/m(95% CI)P valueAnnual weight change, kg/year (95% CI)P value
All754 (100)+5.6 (4.8 to 6.4)+1.8 (1.5 to 2.1)+1.4 (1.0 to 1.8)
Ex-smokerYes509 (67.5)+7.5 (4.3 to 8.6)<0.0001*+2.4 (2.0 to 2.8)<0.0001*+1.6 (1.1 to 2.1)0.0061*
No245 (32.5)+3.7 (2.5 to 4.9)+1.2 (0.8 to 1.6)+0.9 (0.2 to 1.5)
Number of cigarettes smoked per day (n=509)≤10105 (13.9)+5.6 (3.4 to 7.8)<0.0001*+1.8 (1.1 to 2.5)<0.0001*+1.3 (0.3 to 2.2)0.0288*
>10≤25303 (40.1)+7.5 (6.1 to 8.9)+2.4 (2.0 to 2.8)+1.6 (0.9 to 2.3)
>25101 (13.4)+10.2 (7.4 to 13.0)+3.7 (2.8 to 4.6)+1.4 (0.6 to 2.1)
Substance misuseYes379 (50.2)+7.4 (6.1 to 8.7)0.0056*+2.3 (1.9 to 2.7)0.0047*+1.4 (0.8 to 2.8)0.0885
No375 (49.7)+4.5 (3.4 to 5.6)+1.5 (1.2 to 1.8)+1.3 (0.8 to 1.7)
Substance type
(n=379)
Alcohol52 (13.7)+2.6 (−1.1 to 6.3)0.0013*+0.8 (−0.4 to 2.8)0.0013*+0.3 (−0.6 to 1.2)<0.0001*
Drugs229 (60.4)+8.4 (6.9 to 9.9)+2.6 (2.1 to 3.11)+2.6 (1.6 to 3.5)
Both98 (25.9)+6.8 (4.1 to 9.5)+2.1 (1.2 to 3.0)+0.8 (0.1 to 1.5)
Illicit drug misuseYes327 (43.4)+8.0 (6.3 to 9.7)0.0004*+2.4 (2.0 to 2.8)0.0003*+1.7 (1.0 to 2.4)0.0009*
No427 (56.6)+4.5 (3.4 to 5.6)+1.4 (1.1 to 1.7)+1.1 (0.7 to 1.5)
Alcohol misuseYes150 (19.9)+5.5 (3.8 to 7.2)0.4147+1.8 (1.1 to 2.5)0.5435+1.4 (1.0 to 1.8)0.8075
No604 (80.1)+5.8 (4.3 to 7.5)+1.9 (1.6 to 2.2)+1.3 (0.5 to 2.1)
  • Wilcoxon test was used in analyses with two categories (ex-smoker, substance misuse, illicit drug misuse and alcohol misuse). Kruskal-Wallis test was used in analyses with three or more categories (number of cigarettes smoked per day, substance type).

  • *P value <0.05 was considered statistically significant. The average length between admission and follow-up was 5.0±8.3 years.

  • BMI, body mass index.