Osteoarthritis (OA) is the second most common age-related
problem that affects quality of life24 and it is the most frequent
joint disease in India, with a prevalence of 22% to 39%2. OA is more
common in women than men, but the prevalence increases dramatically with age24,25,26. Nearly
45% of women over the age of 65 years have symptoms while radiological evidence
is found in 70% of them25,26,27.
OA was estimated to be the 10th leading cause
of nonfatal burden25,27.OA of the knee is a major cause of mobility
impairment, particularly among females25,26,28,29. Osteoarthritis
accounts for decrease in activities of daily living (ADL) in elderly dependent
population in the community5.
Although osteoarthritis affects both males and females,
prevalence of osteoarthritis reported to increase in females during
peri-menopausal age and remains high throughout menopause as compared to males. Numerous experimental, clinical and epidemiological studies
suggest that loss of estrogen at the time of menopause increase a woman’s risk of
getting osteoarthritis30. Average menopausal age in Indian
women is 46.3 years as compared to 51 years in western countries. 31 This
predisposes Indian women to the risk of developing osteoarthritis at earlier
age compared to their western counterparts.
Salve et al
conducted a study in south Delhi in 2010 regarding the prevalence of knee
osteoarthritis in south Delhi and found that 47.8% women of age >40years
are suffering from knee osteoarthritis32. Elizabeth et al conducted a similar study in urban Bangalore,
and found that the mean age of the population was 42.56 ±16.5 years. The
corresponding prevalence of osteoarthritis calculated using the ACR and the
EULAR 2009 criteria were 17% and 5.6% in the adult population and 54.1% and
16.4% in the elderly>60 years.
Etiological factors found associated with osteoarthritis were age
(p<0.0001), poor education (p<0.0001), previous knee injury (p=0.046), and regular climbing of stairs (p<0.0001)33. Radha et al conducted similar study in Mysore in 2015 with following results: Out of 150 knee osteoarthritis patients, (95 female and 55 male), the prevalence of knee osteoarthritis was highest in the age groups 60-65 and 40-45, and least in the age group 50-55yrs.They concluded that the risk factors for developing knee osteoarthritis are female gender, advancing age, overweight, previous knee injury or surgery34. Patil et al in 2012 conducted a hospital based cross sectional study in Dharwad and also found that OA was more in women compared to men (65.7% vs. 34.3% respectively) and discussed that this difference could possibly be due to the lack of physical activity, mobility, social issues especially in our region and higher prevalence of obesity among women in general35.Another study conducted by Iqbal et al showed the same results, wherein 74 (74%) females and 26 (26%) males showed osteoarthritis. Smokers were 25 (25%), obesity was present in 33 (33%) and anemia was present in 7 (50%) women and 16 (61.5%) males36. The number of women with osteoporosis, i.e., with reduced bone mass and the disruption of bone architecture, is increasing in India. While data on prevalence of osteoporosis among women in India come from studies conducted in small groups spread across the country, estimates suggest that of the 230 million Indians expected to be over the age of 50 years in 2015, 20%, (i.e., ~46 million), are women with osteoporosis. Thus, osteoporosis is a major public health problem in Indian women. The prevalence of osteopenia and osteoporosis has also been reported many times in the past. Tatu& Makinen (2007) reported prevalence of osteoporosis and osteopenia as 28% and 47% respectively37. Risk factors for development of osteoporosis is female sex, advancing age, thin built and ethnicity. Both these diseases (osteoarthritis and osteoporosis)share the same risk factors, but it is debatable whether these diseases coexist, or are mutually exclusive. Jan Dequeker in 1983 stated that osteoarthritis and osteoporosis are two different entities and not the single phenomenon of aging and wear and tear. According to him, women with osteoporosis are thin, shorter, have less fat, girth and less strength while women with osteoarthritis are tall, have more body fat and stronger38. Foss et alalso believed that osteoporosis and osteoarthritis do not normally occur together and that bone density in a patient with osteoarthritis is more than the normal for their age39. Verstraeten et al reviewed 72 women in his study and suggested that osteoarthritis have protective role on the progression of osteoporosis40. In the Framingham study (2000),473 women underwent complete bone density assessment, and the results indicated that high BMD and BMD gain decreased the risk of progression of radiographic knee OA but may be associated with an increased risk of incident knee OA41. Stewart et al (1999) compared the OA patient with history of hip fracture with controls. They found that patients with osteoporosis have lower bone density while patient with osteoarthritis have more BMD as compared to controls42. Contrarily, Schneider et al in the Rancho Bernado study stated that OA was not associated with increased BMD levels in men or women43. Hochberg et al conducteda longitudinal cohort study in 2004, concluding that people with radiographic advanced osteoarthritis have different rate of loosening of bone than those have normal radiograph. They presented the hypothesis of inverse relationship between osteoarthritis and osteoporosis44. Hanan et al in 1993 tried to examine the possible inverse relationship between osteoporosis and osteoarthritis (OA) by evaluating the association between bone mineral density (BMD) and knee OA in the Framingham Study cohort study. A total of 572 women and 360 men were studied, and he found femoral BMD 9% higher than the normal in grade 1,2 &3 OA, and comparable to normal population in grade 4 OA. Further, mean BMD did not differ across levels of joint space narrowing45. Dequeker et al in 2003also observed that people with osteoarthritis have strong body built, are more obese, and have increased BMD at all sites. In these, ageing reduces bone loss, and they have more number of growth factors for bone repair with lesser chances of fragility fractures46. Blain et al reinforced the findings that increased hip fragility in osteoporosis is attributed mainly to a thinning of the cortex, and in contrast, hip osteoarthritis (OA) is not associated with increased risk of hip fracture. They observed that the trabecular pattern decreased by 50% in patients with osteoporosis compared to patient with hip osteoarthritis47.Similar results were presented by Boutroy et al (2011)who compared the 2D and 3D bone microarchitecture evaluation at the femoral neck, among postmenopausal women with hip fracture or hip osteoarthritis and found that trabecular volume is 43% less in patients with hip fracture as compared to patient with hip osteoarthritis48. What about the prevalence of osteoporosis in patients with advanced knee and hip osteoarthritis? Labuda et al in 2008 studied the prevalence of osteoporosis in patients undergoing total knee replacement and found that 26% have osteoporosis and suggested that more research work is required in this field49. James et al however (through a study conducted in United Kingdom in 2014)reported the prevalence of DXA proven hip osteoporosis (T-score ? -2.5) among hip and knee arthroplasty patients to be as low at 2.8%. Spinal osteoporosis prevalence in their cohort was higher at 6.9% . Sixty patients (42% ) had osteopenia or osteoporosis of either the hip or spine11. Sadigursky recently (2017)reported the prevalence of osteoporosis in Brazilian population as 31.7% (decreased bone mass),15% (osteopenia) and 16.7% (confirmed diagnosis of osteoporosis from BMD) 50. Tarjaet al conducted a similar type of study in 2004, comparing the BMD of contralateral knee and both hip preoperatively and postoperatively at 1 year follow up, found that though the post-operative knee status and physical activity (AKS scores) improved, neither the hip nor the nonoperated knee BMDs increased. They concluded that improved mobility after TKA does not improve the effects of preoperative disuse-associated bone loss in the short term51. Tadeusz et al (2008) compared pre-surgery BMD with post-surgery BMD in total knee replacement, and observed decreased BMD around the prosthesis; concluding that the decrease in BMD at the knee joint arthroplasty site is a result of the postoperative increased bone resorption and decreased patient motor activity52 while Arden in 1999 reported that subjects with OA did not have a significantly reduced risk of osteoporotic fracture, although there was a trend toward a reduced risk of femoral neck fractures. They reasoned that failure of the observed increase in BMD to translate into a reduced fracture risk may be due, in part, to the number and type of falls sustained by subjects with OA; and patients with OA should not be considered to be at a lower risk of fracture than the general population. They cautioned that physicians should be aware that a high BMD in patients with OA might be falsely reassuring53. Arden later (2006) however disagreed with his earlier findings and showed that persons with OA knee had increased chances of fall and have greater chances of non vertebral and hip fractures54. Vitamin D deficiency prevails in epidemic proportions all over the Indian subcontinent, with a prevalence of 70%–100% in the general population. Harinarayan through his report confirmed that Vitamin D deficiency is epidemic in India despite of plenty of sunshine55. Ambrish Mithal (2009) also concluded through his multicentric study that hypovitaminosis D is widespread and is re-emerging as a major health problem globally56. Interestingly, insufficient levels of serum 25-hydroxyvitamin D (25-OH vitamin D) influence the knee joint cartilage and can lead to development and progression of knee osteoarthritis (OA). Timothy et al (1996) through the Framingham study found that low intake and low serum levels of vitamin D each appear to be associated with an increased risk for progression of osteoarthritis of the knee17.This was corroborated by Behzad Heidari (2011), who found a significant association between serum 25-OHD deficiency and knee OA in patients aged?60 years and suggested serum 25-OHD measurement in any patient with symptoms suggestive of knee OA particularly at the initial stage of disease57. Lane et al (1999) conducted a study to prove correlation between serum vitamin D levels and incident changes of radiographic hip osteoarthritis. They observed that low serum levels of 25-vitamin D may be associated with incident changes of radiographic hip OA characterized by joint space narrowing58. Heike et al (2005) also found a positive correlation between vit. D level and bone density in osteoarthritis59. David Felson (2006)however concluded that vitamin D status is unrelated to the risk of joint space or cartilage loss in knee OA40. Bergnik et al (2009) found low dietary vitamin D intake led to increased risk of progression of knee OA, particularly in subjects with low baseline BMD; advising that improving the vitamin D status in the elderly could protect against the development and worsening of knee OA, especially in those with low BMD60. Chaganti et al (2010) found that elderly men with radiographic hip OA have a high prevalence of 25(OH)D deficiency. Since 25(OH) vitamin D has a significant role in the maintenance of bone and cartilage, therapeutic interventions with vitamin D to augment skeletal health in the elderly are warranted62. Muraki et al (2011) indicated that vitamin D deficiency may be associated with pain rather than radiographic changes63. 23