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Purpose

The purpose of this study was to determine the prevalence of respiratory and/or physical fitness health problems in adolescent (ages 18–21) water pipe (WP) smokers (with or without cigarette smoking), cigarette-only smokers, and nonsmokers.

Methods

A comparative four-group study design was used to recruit a non–probability sample of 153 WP smokers only, 103 cigarette smokers only, and 102 cigarette+WP smokers along with 296 nonsmokers. Our hypothesis was that youth who smoked WPs and/or cigarettes would report more respiratory problems and/or poorer physical fitness than those who did not smoke.

Results

The results showed that coughs were significantly associated with smoking in all three of the smoking groups (p < .05). Cigarette-only smokers reported the most adverse outcomes with more wheezing, difficulty breathing, and less ability to exercise without shortness of breath. A dose-response analysis showed similar patterns of adverse health effects for both WP and cigarette smokers. The combined use of both products was not appreciably worse than smoking one product alone. This could be due to cigarette+WP smokers' reporting using less of the respective products when only one product was smoked.

Conclusions

Even during the adolescent years, WP and/or cigarette smoking youth experienced reportable negative health effects.  相似文献   
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Access to safe and effective contraceptive choices is a reproductive right and contributes tremendously to improvements in maternal and child health. Progestin-only injectables, particularly intramuscularly injected depot medroxyprogesterone acetate (DMPA-IM), have received increased attention given findings suggesting a potential association with increased HIV risk. For women at high risk of HIV, the World Health Organization's Medical eligibility criteria for contraceptive use currently aggregate recommendations for all progestin-only injectables, including DMPA-IM, subcutaneously injected DMPA (DMPA-SC) and intramuscularly injected norethindrone/ norethisterone enanthate (NET-EN), except in the case of some drug interactions. We considered whether published data indicate differences or similarities between these injectables relevant to risk of acquiring HIV. In vitro data confirm different biological activities of these distinct progestins, including that MPA, and not NET, binds and activates the glucocorticoid receptor resulting in different biological effects relevant to immune function. Limited clinical data suggest changes in immunologic activity following DMPA-IM and NET-EN initiation, but interstudy variation and study design differences diminish ability to determine clinical relevance and the degree to which DMPA-IM and NET-EN could act differentially. The highest-quality epidemiologic studies suggest a potential 40% increase in HIV incidence in users of DMPA-IM relative to women not using hormonal contraception but no significant increase in risk in users of NET-EN. In our opinion, most of the available biologic activity and epidemiologic data indicate that DMPA and NET-EN are likely to act differently, and data remain too limited to evaluate differences between DMPA-IM and DMPA-SC.  相似文献   
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The Patient - Patient-Centered Outcomes Research -  相似文献   
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