Context: Young women are at high risk of weight gain but there has been limited knowledge on weight management in this group. Hyperandrogenemia and menstrual abnormalities are common co-morbidities of obesity in young women but their associations with food cravings are not known. Metformin has been shown to reduce body weight and improve metabolic outcomes in older adults but its effects on healthy overweight and obese young women have not been investigated. Quantitative lifestyle advice has been shown to be effective in inducing weight loss but its psychological effects on young women have not been extensively studied. The overall objective of this study was to investigate the effectiveness of metformin, quantitative lifestyle advice and internet-based intervention on weight management in young. Methods: In the first 12-weeks, 203 overweight and obese young women (BMI 33.3±0.3 kg/m² , age 28±0.3 years; age range:17-37) were randomized to one of three treatment arms to receive metformin (Diabex XR 1500mg a day) plus qualitative lifestyle advice (M-QL), placebo plus qualitative lifestyle advice (P-QL) or a structured lifestyle program (L-QT). L-QT consisted of an energy restricted diet with quantitative lifestyle advice (6000KJ; 40% protein, 40% carbohydrate, 30% fat), structured exercise program, and behavioural therapy. From weeks 13 to 48, all participants were placed on the structured lifestyle program conducted through a website. Outcome measures include body weight, fasting lipids, insulin, glucose, psychological distress, self-esteem, food cravings, energy intake and physical activity. Primary analyses were conducted using linear mixed models. Results: At baseline, psychological distress and hyperandrogenemia were associated with increased food cravings (P<0.01). At 12-weeks, L-QT group had greater weight loss (-4.2±0.4 kg) compared to M-QL (-1.0±0.4 kg) and P-QL groups (-0.2±0.3 kg) (P<0.001). Attrition at week 12 was high particularly in L-QT group, ie 48% (28/59) for L-QT group, 34% (22/65) for M-QL group and 29% (23/79) for P-QL group (P=0.08). Baseline psychological distress and food cravings predicted attrition at week 12. At week 12, L-QT group had significantly greater improvements in psychological distress (-3.0+0.9 vs -0.84+0.52, P=0.013) and self-esteem (3.2±0.8 vs -0.04±0.4, P<0.001) compared to the M-QL and P-QL groups. At 48 weeks, both QT and QL groups maintained significant weight loss (-4.8±0.1 kg vs -1.3±0.4 kg respectively, P=0.0005). Weight changes from week 13 to 48 were similar between the groups (P>0.05). Attrition was similarly high in both groups by week 48 (78%; 159/203) (P=0.003). Being married or having children predicted attrition at week 48. Conclusions: A structured lifestyle intervention program was more effective than metformin in achieving weight loss in young women. Quantitative lifestyle advice produced greater improvements in psychological outcomes compared to qualitative lifestyle advice. Internet-based weight loss program was effective in maintaining weight loss in young women independent of initial weight loss. High attrition rates were seen throughout the study, particularly among those who had greater psychological distress or food cravings, and those who were married or had children. Strategies on managing issues relating to psychological distress, food cravings and family responsibilities may allow better tailoring of weight management programs for this group. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1523605 / Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2009

Context: Young women are at high risk of weight gain but there has been limited knowledge on weight management in this group. Hyperandrogenemia and menstrual abnormalities are common co-morbidities of obesity in young women but their associations with food cravings are not known. Metformin has been shown to reduce body weight and improve metabolic outcomes in older adults but its effects on healthy overweight and obese young women have not been investigated. Quantitative lifestyle advice has been shown to be effective in inducing weight loss but its psychological effects on young women have not been extensively studied. The overall objective of this study was to investigate the effectiveness of metformin, quantitative lifestyle advice and internet-based intervention on weight management in young. Methods: In the first 12-weeks, 203 overweight and obese young women (BMI 33.3±0.3 kg/m² , age 28±0.3 years; age range:17-37) were randomized to one of three treatment arms to receive metformin (Diabex XR 1500mg a day) plus qualitative lifestyle advice (M-QL), placebo plus qualitative lifestyle advice (P-QL) or a structured lifestyle program (L-QT). L-QT consisted of an energy restricted diet with quantitative lifestyle advice (6000KJ; 40% protein, 40% carbohydrate, 30% fat), structured exercise program, and behavioural therapy. From weeks 13 to 48, all participants were placed on the structured lifestyle program conducted through a website. Outcome measures include body weight, fasting lipids, insulin, glucose, psychological distress, self-esteem, food cravings, energy intake and physical activity. Primary analyses were conducted using linear mixed models. Results: At baseline, psychological distress and hyperandrogenemia were associated with increased food cravings (P<0.01). At 12-weeks, L-QT group had greater weight loss (-4.2±0.4 kg) compared to M-QL (-1.0±0.4 kg) and P-QL groups (-0.2±0.3 kg) (P<0.001). Attrition at week 12 was high particularly in L-QT group, ie 48% (28/59) for L-QT group, 34% (22/65) for M-QL group and 29% (23/79) for P-QL group (P=0.08). Baseline psychological distress and food cravings predicted attrition at week 12. At week 12, L-QT group had significantly greater improvements in psychological distress (-3.0+0.9 vs -0.84+0.52, P=0.013) and self-esteem (3.2±0.8 vs -0.04±0.4, P<0.001) compared to the M-QL and P-QL groups. At 48 weeks, both QT and QL groups maintained significant weight loss (-4.8±0.1 kg vs -1.3±0.4 kg respectively, P=0.0005). Weight changes from week 13 to 48 were similar between the groups (P>0.05). Attrition was similarly high in both groups by week 48 (78%; 159/203) (P=0.003). Being married or having children predicted attrition at week 48. Conclusions: A structured lifestyle intervention program was more effective than metformin in achieving weight loss in young women. Quantitative lifestyle advice produced greater improvements in psychological outcomes compared to qualitative lifestyle advice. Internet-based weight loss program was effective in maintaining weight loss in young women independent of initial weight loss. High attrition rates were seen throughout the study, particularly among those who had greater psychological distress or food cravings, and those who were married or had children. Strategies on managing issues relating to psychological distress, food cravings and family responsibilities may allow better tailoring of weight management programs for this group. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1523605 / Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2009