Assessment of Medication Adherence and Factors Contributing to Non-Adherence to Calcium and Vitamin D as Mainstay in Treatment and Prophylaxis of Osteoporosis
Authors: Al-Adawi Rana Moustafa , Jassim Zainab Malik 
Published: July 2019

Objective

This study aimed to assess the adherence and persistence to Calcium and vitamin D, and address the reasons of non-adherence.

Methods

All patients attending a secondary care rheumatology clinic in a teaching hospital serving a multiethnic population, in the period between April and June fulfill the inclusion criteria. Patients were asked verbally before distributing the question air about the duration and reason of prescribed Calcium and vitamin D, only patients who are receiving Calcium and Vitamin D for duration of one year or more for purpose of osteoporosis management (treatment and prophylaxis) and are welling to participate in the question are were given the consent formand included in the study.

Key finding

There was no statistically significant difference between calcium and vitamin D group in terms of adherence score (p =  0.175). About third of patients in both groups showed low adherence score; 31% (53/171), 38.2% (128/335) in calcium and vitamin D groups, respectively. Overall, there was significant difference in adherence score between age groups (p = 0.001). Low adherence score was mostly reported in young age group (18–39 years) for both medications but not related to level of education. Forget to take medication was the most reported reason of non adherence in both groups (29.5%, 89/302). Quarter of patients stated that multi-reasons contributed to their non adherence (24.8%, 75/302).

Conclusion

Low adherence was high among both Calcium and Vitamin D groups (around third of both groups), however; there were no significant differences in medications adherence between the two groups

Keywords

Adherence, osteoporosis, treatment and prophylaxis

Introduction

Osteoporosis has been defined by national and international organizations by either describing the outcomes or on the bases of Bone Mineral Density (BMD) or bone turnover markers (BTMs). The World Health Organization (WHO) 1994 defined Osteoporosis as “a disease characterized by low bone mass and micro-architectural deterioration of bone tissue, enhanced bone fragility and a consequent increase in fracture risk” (Kanis JA, et al., 1994, pp; 1137–41). On the bases of Bone Mineral Density (BMD), WHO 1994 defined Osteoporosis as BMD at hip or spine, that is less than or equal to 2.5 standard deviation below the young normal adult. While National Osteoporosis Foundation (NOF, 2010) defined the Osteoporosis as “a silent disease until it is complicated by fractures—fractures that can occur following minimal trauma. Usually causes no signs or symptoms except height loss and kyphosis until fracture occurs”. Osteoporosis became a major worldwide concern, due its high prevalence that will increase in the coming years due to the significant increase in life expectancy. The prevalence of Osteoporosis will continue to rise with the predicted demographic expulsion. According to IOF fast fact sheet (2011), about 1 in 2 Asian and Caucasian women and 1 in 4 Asian and Caucasian men over age 50 will have an Osteoporosis-related fracture in their life that will decrease their quality of life. Osteoporosis causes more than 8.9 million fractures annually worldwide (WHO, 2004 a). In the UK Osteoporosis affects 2 million people and is responsible for more than 300,000 fragility fractures per year. About 70,000 people suffer from hip fractures annually with about 1,150 of them dying every year. UK has one of the highest rates of Osteoporosis related fractures in Europe (Paul Mitchell, 2010). In Canada, Osteoporosis is estimated to affect women with rate of 12.1% at lumbar spine, 7.9% at the femoral neck, with a combined prevalence of 15.8%, while affecting men in rate of 2.9 % at lumbar spine and 4.8% at the femoral neck with a combined prevalence of 6.6%. (A. Tenenhouse, et al, 2000). While in China, Osteoporosis prevalence was 16.1% (LI Ninghua, et al, 2002). 31 Concerning Qatar and Osteoporosis, Hammoudeh M, et al. (2005:319–327) state “Osteoporosis is common among menopausal Qatari women and should be considered as a matter of public concern.” This was concluded through his cross-sectional study that examined 574 Qatari women between ages 20–69. The study aimed to determine the reference value for Qatari women and compare them with values from Western and other Arab countries. Finally, this study showed that BMD values of Qatari women are lower than Caucasians and Kuwaitis at the spine and the total femur in age group 60–69 years, but higher in values of total femur in the age group 40–59. Medical care and pharmacological treatment of Osteoporosis are currently available, including calcium (1200 mg daily intake) and vitamin D (800–1000 IU daily intake) as a mainstay of osteoporotic treatment along with an ant-osteoporotic medication such as Bisphosphonates, parathyroid hormone, the selective estrogen receptor modulator (raloxifene), calcitonin, denosumab and one anabolic agent (teriparatide) (Cranney A, et al., 2002). The importance of calcium and vitamin D supplementation in reduction of osteoporosis risk and osteoporosis related fracture risk is usually overlooked by patients and health care provider, so the standard care of osteoporosis should emphasis on optimal Calcium and Vitamin D supplementation. Many studies evaluate the relation between dietary or supplemental calcium intake in addition to vitamin D supplementation on the risk of osteoporosis and increased osteoporosis fracture, where in 2008–2009, heok hong, et al., evaluate in his study the BMD of adult Korean population after dividing them in to 4 quarters, to show that the q4 is high BMD than the other groups Q1 & Q2. (Q4 which had highest calcium intake). Additionally Wlodarek, 2012 and Higahuchi M, 2010 stated in their studies that, the higher the calcium intake the higher the BMD will increase. As well as Reid IR et al., 1995 & 1998 mentioned in his studies that calcium intake is linked with a00202–10% increment in BMD and 35–50% reduction in fracture risk The effectiveness of the medication not only depends on the efficacy of the medication but also on the compliance and persistence to prescribed medication. Adherence is essential to achieve the maximal benefit. Therefore in this study we are going to assess the adherence to Cal/Vit D and address the reasons of the non-adherence, in order to find ways to overcome these problems improve compliance and enhance the efficacy and improve the patient's quality of life