Smoking cessation—but not smoking reduction—improves the annual decline in FEV1 in occupationally exposed workers

SummaryIntroductionIndividuals exposed both to cigarette smoke and respiratory pollutants at work incur a greater risk of development of airway hyperresponsiveness (AHR) and accelerated decline in forced expiratory volume in 1s (FEV1) than that incurred by subjects undergoing each exposure separately. We examined whether smoking cessation or smoking reduction improves AHR and thereby slows down the decline in FEV1 in occupationally exposed workers.MethodsWe examined 165 workers (137 males and 28 females) participating in a smoking cessation programme. Nicotine tablets were used for smoking cessation or smoking reduction. Respiratory symptoms were assessed by questionnaire, FEV1 by spirometry and AHR by methacholine challenge test. At 1 year, subjects were classified into quitters, reducers, or continuing smokers.ResultsSixty-seven subjects completed the study (32 quitters; 17 reducers; 18 continuing smokers). Respiratory symptoms improved markedly in quitters (P<0.001 for all comparisons) and less so in reducers (P values between 0.163 and 0.027). At 1 year, FEV1 had slightly but significantly improved in quitters (P=0.006 vs. smokers; P=0.038 vs. reducers) and markedly deteriorated in reducers and continuing smokers. Concurrent, 1-year change in AHR did not differ significantly among the groups.ConclusionIn occupationally exposed workers, stopping smoking markedly improved respiratory symptoms and, in males, slowed the annual decline in FEV1. Smoking reduction resulted in smaller improvements in symptoms but deterioration in FEV1. These findings were independent of AHR. While smoking cessation should remain the ultimate goal in workplace cessation programmes more studies are necessary to better ascertain the benefits of smoking reduction

Diet, growth, and the risk for type 1 diabetes in childhood: a matched case-referent study.

OBJECTIVE: To study the association between type 1 diabetes risk and previous intake of energy, accounting for body size and previous intake of nutrients and foods, accounting for the energy intake. RESEARCH DESIGN AND METHODS: We conducted an incident population-based case-referent study in Stockholm, Sweden, including 99 of 100 eligible 7- to 14-year-old diabetic children and 180 of 200 age-, sex-, and area-matched referent children identified through the Swedish population register. Average daily energy and nutrient intake 1 year before diabetes diagnosis/interview was estimated using the food frequency questionnaire with assessment of consumed food amounts. Mean SD scores of growth measurements taken during the last 4 years before the diagnosis were used. Odds ratios (ORs) were calculated by conditional logistic regression. RESULTS: Average intake of energy, carbohydrate, fat, and protein was significantly higher among the case subjects as well as mean weight-for-age SD score. Higher energy intake and weight-for-age were both associated with increased diabetes risk after adjustment for each other: OR (95% CI) for medium and high levels of energy intake were 1.33 (0.52-3.42) and 5.23 (1.67-16.38), respectively, and for weight-for-age were 3.20 (1.30-7.88) and 3.09 (1.16-8.22), respectively. High intake of carbohydrates, especially disaccharides and sucrose, increased diabetes risk. CONCLUSIONS: Higher energy intake and larger body size were independently associated with increased diabetes risk. Of the different nutrients, higher intake of carbohydrates, particularly disaccharides and sucrose, increased the risk. Lifestyle habits leading to higher energy intake and more rapid growth in childhood may contribute to the increase of childhood-onset type 1 diabetes by different mechanisms