Reumatismo. 2013 Jul 23;65(3):113-20. doi: 10.4081/reumatismo.2013.113.
Rossini M, D'Avola G, Muratore M, Malavolta N, Silveri F, Bianchi G, Frediani B, Minisola G, Sorgi ML, Varenna M, Foti R, Tartarelli G, Orsolini G, Adami S, Italian Society Of Rheumatology Sir OB.
Rheumatology Unit, University of Verona. maurizio.rossini at univr.it.
Vitamin D deficiency is very common in patients with rheumatoid arthritis (RA). Aim of this study was to evaluate the prevalence of vitamin D deficiency among the different Italian regions and whether these variations are associated with different severity of the disease. The study includes 581 consecutive RA patients (464 women), not taking vitamin D supplements, from 22 Italian rheumatology centres uniformly distributed across Italy. Together with parameters of disease activity (disease activity score 28), functional impairment (activities of daily living and health assessment questionnaire disability index) and mean sun exposure time, all patients had serum 25-hydroxyvitamin D (25OHD) measured in a centralized laboratory.
Vitamin D deficiency (25OHD level < 20 ng/mL) was very frequent among RA patients; its prevalence was 60%, 52% and 38% in southern, central and northern Italy, respectively. Mean disease activity and disability scores were worse in southern regions of Italy. These scores were inversely related to 25OHD levels and this correlation remained statistically significant after adjusting for both body mass index (BMI) and sun exposure time. However, disease severity remained significantly higher in southern regions versus central-northern Italy after adjustment also for serum 25OHD levels, age and BMI. In RA Italian patients there are significant regional differences in the prevalence of vitamin D deficiency explained by different BMI, and sun exposure time, and inversely associated with disease activity and disability scores.
Many places around the world are now able to totally avoid the hot summer sun by using air conditioning.
The Middle East, for example, avoids the summer sun so much that the flu comes in the summer instead of the winter.
The people living in the Southern portion of the US appear to be using air conditioning so much that the latitude affect of MS reversed by the middle of the century
- Diabetes rising quickly in areas with recent air conditioning – June 2011
- Hypothesis – China air conditioning disease is the result of less vitamin D – March 2011
- Air conditioning has not totally canceled the latitude effective in the US yet – July 2013
- Air Conditioning probably has decreased vitamin D which has the following graphic