Weight gain and adipose tissue metabolism after smoking cessation in women

Cigarette smoking increases the risk of cardiovascular disease, and is an important preventable cause of death and illness. One major deterrent to smoking cessation is a gain in body weight. Understanding the mechanisms that contribute to this weight gain may maximize the success of long-term smoking cessation. We hypothesized that smoking cessation is associated with an increase in adipose tissue lipoprotein lipase (AT-LPL) activity and/or a decrease in lipolysis, two metabolic factors that determine the balance between fat storage and fat utilization, and thus affect the propensity for weight gain.

Ten premenopausal women (37.1+/-6.2 y, 31.7+/-6.4 kg/m(2) body mass index (BMI), mean+/-s.d.) participated in a 4 week smoking cessation program. Measurements of body weight, waist and hip circumferences, adipose cell metabolism and resting metabolic rate were obtained at baseline and after 4 weeks of smoking cessation.

Of the 10 women who began the intervention, five successfully completed the smoking cessation intervention. After 4 weeks of smoking cessation, there were significant increases in body weight (95.1+/-13.9-97.7+/-14.4 kg, P<0.05), with no change in waist and hip circumferences or resting energy expenditure. Gluteal AT-LPL activity significantly increased in all women by 2.8-fold (1.65+/-1.30-4.72+/-3.34 nmol/g/min, P<0.05). Abdominal AT-LPL activity increased in four out of the five women, but did not reach statistical significance (1.14+/-0.88-3.50+/-3.76 nmol/g/min, P=0.14). The increase in body weight correlated with the increase in gluteal AT-LPL activity (r=0.89, P<0.05), as well as the baseline activity of gluteal AT-LPL (r=0.86, P=0.06). There were no changes in basal or stimulated lipolysis in the gluteal or abdominal fat depots.

These results suggest that smoking cessation is associated with significant increases in body weight, as well as changes in adipose cell metabolism, in particular increases in AT-LPL activity. This increase in LPL activity may contribute to the increase in body weight associated with smoking cessation.