title: Variation in treatment strategies of Swiss general practitioners for subclinical hypothyroidism in older adults.
abstract: OBJECTIVE
  As the best management of subclinical hypothyroidism is controversial, we aimed to assess variations in treatment strategies depending on different Swiss regions, physician and patient characteristics.
  
  
  METHODS
  We performed a case-based survey among general practitioners (GPs) in different Swiss regions, which consisted of eight hypothetical cases presenting a female patient with subclinical hypothyroidism and nonspecific complaints differing by age, vitality status and thyroid-stimulating hormone (TSH) concentration.
  
  
  RESULTS
  A total of 262 GPs participated in the survey. There was considerable variation in the levothyroxine starting dose chosen by GPs, ranging from 25 µg to 100 µg. Across the Swiss regions, GPs in the Bern region were significantly more inclined to treat, with a higher probability of initiating treatment (60%, p = 0.01) and higher mean starting doses (45 µg, p <0.01) compared with the French-speaking region (44%, 36 µg); the Zurich region had intermediate values (52%, 39 µg). We found no association between treatment rate and other physician characteristics. GPs were more reluctant to initiate treatment in 85-year-old than in 70-year-old women (odds ratio [OR] 0.77, 95% confidence interval [CI] 0.63-0.94), and more likely to treat women with a TSH of 15 mU/l than those with a TSH of 6mU/l (OR 8.71, 95% CI 6.21-12.20).
  
  
  CONCLUSIONS
  There are strong variations in treatment strategies for elderly patients with subclinical hypothyroidism across different Swiss regions, including use of higher starting doses than the recommended 25 µg in the Swiss guidelines, which recommend a starting dose of 25 µg. These variations likely reflect the current uncertainty about the benefits of treatment, which arise from the current lack of evidence from adequately powered clinical trials.
authors.affiliation: Department of General Internal Medicine, Inselspital, University of Bern, Switzerland.
authors.forename: Christine
authors.initials: C
authors.lastname: Baumgartner
authors.affiliation: Department of Public Health and Primary Care, Leiden University Medical Centre, Leiden, the Netherlands.
authors.forename: Wendy P J
authors.initials: WP
authors.lastname: den Elzen
authors.affiliation: Department of General Internal Medicine, Inselspital, University of Bern, Switzerland.
authors.forename: Manuel R
authors.initials: MR
authors.lastname: Blum
authors.affiliation: CTU Bern, Department of Clinical Research, and Institute of Social and Preventive Medicine (ISPM), University of Bern, Switzerland.
authors.forename: Michael
authors.initials: M
authors.lastname: Coslovsky
authors.affiliation: Department of General Internal Medicine, Inselspital, University of Bern, Switzerland, and Bern Institute of General Practice, University of Bern, Switzerland.
authors.forename: Sven
authors.initials: S
authors.lastname: Streit
authors.affiliation: Bern Institute of General Practice, University of Bern, Switzerland.
authors.forename: Peter
authors.initials: P
authors.lastname: Frey
authors.affiliation: Institute of General Medicine, University of Lausanne, Switzerland.
authors.forename: Lilli
authors.initials: L
authors.lastname: Herzig
authors.affiliation: Primary Care Unit, University of Geneva, Switzerland.
authors.forename: Dagmar M
authors.initials: DM
authors.lastname: Haller
authors.affiliation: Department of Gerontology and Geriatrics, Leiden University Medical Center, Leiden, the Netherlands, and Institute for Evidence-based Medicine in Old age (IEMO), Leiden, the Netherlands.
authors.forename: Simon P
authors.initials: SP
authors.lastname: Mooijaart
authors.affiliation: Institute of General Medicine, University of Lausanne, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bischoff
authors.affiliation: Institute of General Practice and Health Services Research, University of Zürich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Rosemann
authors.affiliation: Department of Public Health and Primary Care, Leiden University Medical Centre, Leiden, the Netherlands.
authors.forename: Jacobijn
authors.initials: J
authors.lastname: Gussekloo
authors.affiliation: Department of General Internal Medicine, Inselspital, University of Bern, Switzerland.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Rodondi
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D058005:General Practitioners / Q000706:statistics & numerical data*; D020249:Hormone Replacement Therapy / Q000379:methods*; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000188:drug therapy*; D008297:Male; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D012737:Sex Factors; D013557:Switzerland; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000008:administration & dosage*
chemical_list: D013972:Thyrotropin; D013974:Thyroxine