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Table of Contents
Year : 2019  |  Volume : 20  |  Issue : 1  |  Page : 22-27

Risk factors and knowledge of osteoporosis in rural pre-menopausal women

1 School Nurse, Dawha School, Sharjah, United Arab Emirates
2 College of Nursing, CMC, Vellore, Tamil Nadu, India
3 Department of Endocrinology, CMC, Vellore, Tamil Nadu, India
4 Department of Biostatistics, CMC, Vellore, Tamil Nadu, India

Date of Web Publication09-Oct-2019

Correspondence Address:
Mrs. Anmery Varghese
School Nurse, Dawha School, P.O. Box 5914, Sharjah
United Arab Emirates
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/IJCN.IJCN_12_19

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Osteoporosis is one of the major qualities of life-threatening diseases affecting women. It affects one in three women over 50 years of age. The aim of the study was to assess the risk factors and knowledge of osteoporosis among pre-menopausal women in selected rural population in Vellore district, Tamil Nadu. A cross-sectional descriptive research design was used to assess the risk factors and knowledge of osteoporosis. A total of 110 samples between 40 and 50 years of age were selected using convenient sampling technique. Data were collected using the Fracture Risk Assessment Tool® by World Health Organisation, International Physical Activity Questionnaire, Food Frequency Questionnaire, 24 h dietary recall and modified Osteoporosis Knowledge Assessment Tool. The mean age of the women in the study was 43.96 years. Majority (98.18%) of the women had high level of physical activity. The mean intake of calorie and calcium were 1630.81 kcal/day and 310 mg/day, respectively. Majority (86.36%) of the women had low calorie intake, and all the women (100%) had inadequate calcium intake. Most (92.73%) of the women had 1%–2% of 10-year probability of major osteoporotic fracture risk and 105 (95.45%) had <0.5% of 10-year probability of major hip fracture risk. Poor level of knowledge was found among (30.91%), 49.09% had fair knowledge, 17.27% had good knowledge and only 2.73% had very good knowledge regarding osteoporosis. There was a significant association between knowledge of women regarding osteoporosis and their education (P < 0.01) and monthly family income (P < 0.01). There was a significant association of 10-year probability of major osteoporotic fracture risk with calcium supplements (P < 0.01). There was a significant association of 10-year probability of hip fracture risk with occupation (P < 0.01). The findings of the study suggest that there is a need to educate women regarding prevention of osteoporosis. Public health strategies should be aimed at improving the calcium intake of women in this age group and to make appreciable lifestyle changes such as reduction in sedentary lifestyle and increased physical activity.

Keywords: Fracture risk, osteoporosis, physical activity, knowledge, premenopausal women

How to cite this article:
Varghese A, Siva R, Paul TV, Selvaraj KG. Risk factors and knowledge of osteoporosis in rural pre-menopausal women. Indian J Cont Nsg Edn 2019;20:22-7

How to cite this URL:
Varghese A, Siva R, Paul TV, Selvaraj KG. Risk factors and knowledge of osteoporosis in rural pre-menopausal women. Indian J Cont Nsg Edn [serial online] 2019 [cited 2022 Dec 6];20:22-7. Available from: https://www.ijcne.org/text.asp?2019/20/1/22/268690

  Introduction Top

Osteoporosis affecting mostly women is one of the diseases that reduce the quality of life significantly. It is responsible for millions of fractures annually, mostly involving the vertebrae, hip and wrist. The annual number of osteoporotic fractures in women is greater than the total number of cases of heart attacks, strokes and breast cancer combined.[1] Osteoporosis has been defined by the World Health Organisation (WHO)[2] as 'low bone mass and microarchitectural deterioration of bone tissue, leading to enhanced bone fragility and a consequent increase in fracture'. The word osteoporosis literally means 'porous bones'. Osteoporosis is often called the 'silent disease' because bone loss occurs without symptoms. In many cases, the first 'symptom' is a broken bone.

Osteoporosis causes a great deal of morbidity and mortality worldwide. The worldwide cost burden of osteoporosis is expected to increase to almost 106 billion (Euros) by 2050.[3] The International Osteoporosis Foundation[4] claims that osteoporosis affects 1 in 3 women and 1 in 12 men over 50 years of age. More than 200 million women worldwide have osteoporosis. Osteoporosis affects an estimated 75 million people in Europe, USA and Japan. In Europe, the disability due to osteoporosis is greater than that caused by cancers (with the exception of lung cancer) and is comparable or greater than that lost to a variety of chronic non-communicable diseases, such as rheumatoid arthritis, asthma and high blood pressure-related heart disease.[5] It is projected that more than 50% of all osteoporotic hip fractures will occur in Asia by the year 2050. Osteoporosis is a slowly progressive disease and becoming public health problem in Asian countries, including India. Disability due to hip or vertebral fracture is the major concern for the prevention of osteoporosis.[6] Osteoporosis is greatly underdiagnosed and undertreated in Asia, even in the most high-risk patients who have already sustained fractures. The problem is particularly acute in rural areas.[7]

Low bone mass density (BMD) is the determinant of osteoporosis. Low bone mass is because of poor calcium intake, lack of physical exercises and a sedentary life.[8] Calcium intake, physical activity and lifestyle are modifiable risk factors of osteoporosis and with educational strategies focusing on these risk factors, the impact of osteoporosis can be reduced.[9] Despite the high prevalence and serious medical consequences of osteoporosis, many at-risk patients are inadequately screened and diagnosed before symptomatic fractures occur. Failure to identify patients at risk for osteoporosis and fracture results in missed opportunities for prevention. It is important to identify individuals at high risk of osteoporosis and to implement preventive strategies. Efforts to decrease the incidence of osteoporosis include population-based intervention strategies targeted at decreasing the risk factors for osteoporosis, promoting early identification of risk factors and encouraging the adoption of risk-reducing behaviours in the community. Hence, this study was undertaken to identify the risk factors and knowledge of osteoporosis in rural pre-menopausal women. In this study, risk factors of osteoporosis referred to factors which are modifiable and non-modifiable that contributes to the development of osteoporosis. Modifiable risk factors include low body weight, low calcium intake, caffeine intake and inadequate physical activity. Non-modifiable risk factors include age, female gender, previous history of fracture, parent fractured hip and rheumatoid arthritis.

Objectives of the study

The main objectives of the study are as follows:

  • To identify the risk factors of osteoporosis and osteoporotic fracture in rural pre-menopausal women
  • To assess knowledge of pre-menopausal women regarding osteoporosis
  • To determine the association between the knowledge and the selected demographic variables of pre-menopausal women
  • To find the association between fracture risk and the selected demographic variables of pre-menopausal women.

  Methods Top

A cross-sectional descriptive research design was used to assess the risk factors and knowledge of osteoporosis among rural pre-menopausal women. The study was conducted in three villages under the Arcot block. The researcher conducted a house-to-house survey to identify the accessible population and made a sampling framework. From the sampling frame, the participants who fulfilled the inclusion criteria were selected for the study by convenient sampling method. The sample size was 110. It was calculated using the formula 4 pq/d2 where P = 50% with 10% of precision. The sample included pre-menopausal women residing in the selected rural population who were between 40 and 50 years of age who were able to speak and understand Tamil and those who were willing to participate. Women who were pregnant, lactating mothers and woman with co-morbid conditions were excluded from the study.


Part I: Demography-related factors

This included items related to characteristics such as age, weight, education, occupation, marital status, number of children, family history of osteoporosis, dietary habits, calcium supplements and use of oral contraceptives.

Part II: Fracture Risk Assessment Tool

The Fracture Risk Assessment Tool (FRAX®) was developed by the WHO task force in 2008 to evaluate fracture risk of patients.[10]

It includes clinical risk factors such as history of previous fracture, history of hip fracture in parent, smoking, alcohol, intake of glucocorticoids, history of rheumatoid arthritis and body mass index (BMI) which are used to calculate 10-year probability of major osteoporotic or hip fracture.

Part III: International Physical Activity Questionnaire

The International Physical Activity Questionnaire (IPAQ) was used to assess the physical activities of each sample for the last 7 days from the day of administration of the tool.

IPAQ assesses physical activity undertaken across a comprehensive set of domains including: work-related physical activity, transport-related physical activity, domestic and gardening (yard) activities and leisure time physical activity.[11]

The total MET scores were interpreted as follows:

  • Low physical activity = MET score <600/week
  • Moderate physical activity = MET score is 600–3000/week
  • High physical activity = MET score more than 3000/week.

Part IV: Household physical activity tool

This is a part of physical activity tool. It was used to assess the daily physical activities of each sample for the last 7 days from the day of administration of the tool. It has 14 routine household activities such as caring for a child, caring an elderly and cooking meals. It contains 14 routine household activities and the time spent on each of the activity was entered in minutes.

Part V: Food Frequency Questionnaire

This tool was used to assess the practice of intake of dietary calcium for the last 7 days from the day of administration of the tool. It has six subparts: (i) milk and milk products; (ii) meat, fish and eggs; (iii) Nuts, (iv) cereals and pulses; (v) vegetables and (vi) fruits. It contains 94 items. The answer was coded by assigning 0 for not taken, and if taken 1 for daily, 2 for more than three times, 3 for thrice a week, 4 for twice a week and 5 for once a week. The lower the mean score the higher the intake if taken.

Part VI: 24 hours dietary recall

The dietary calorie and calcium intake were calculated using 24-h recall of food intake for each sample with the use of standardised pre-measured nutritional assessment cups. The amount of calcium present in the food item was estimated in milligrams using the nutritive value of Indian foods chart.[12] The obtained value was compared with the recommended daily calcium and calorie intake for an Indian woman by the ICMR expert group (2009). The recommended calorie for women is: Sedentary work: 1900 KCal, Moderate: 2230 Kcal, Heavy work: 2850 Kcal and the calcium is 600 mg/day for all women.

Part VII: Questionnaire on knowledge

To assess the knowledge of pre-menopausal women, the investigator used Osteoporosis Knowledge Assessment Tool after modification. This tool was originally developed by Winzenburg, Oldenburg, Frendin and Jones.[13] This consisted of 20 questions related their knowledge regarding osteoporosis. The answer was coded by assigning 1 for the correct answer and 0 for the incorrect answer. The total scores were converted into percentages and interpreted as follows:

  • Very good knowledge : 80%–100%
  • Good knowledge : 60%–79.9%
  • Fair knowledge : 40%–59.9%
  • Poor knowledge : <40%.

Validity and reliability

Content validity for the modified knowledge questionnaire was established by the review of instrument by the experts from the field of medicine, community health nursing and statistics. The content validity of each item was calculated and the Content Validity Index (CVI) was 0.92. After content validity, the tools were translated into Tamil and back-translation was done. The validity and feasibility of the methodology and instrument was checked by conducting the pilot study.

Data collection procedure

The interview with the study participants was conducted to assess the risk factors and the knowledge of osteoporosis among rural pre-menopausal women, which lasted for 45 min. Every day an average of 4–5 participants were interviewed. The data were collected over 1½ months. The study was conducted after the approval by the Research Committee of the College. Permission was obtained from the Head of the Community Health Nursing Department. Participants gave written informed consent.

  Results And Discussion Top

In the present study, half (50%) of the women were between the age group of 40–45 years and the mean age of women was 43.96 (Standard deviation ± 2.52). Majority of them were either illiterate (30%) or had up to primary level education (51.82%). Most of them did not work outside home (63.63) and were involved in household work. Another major proportion (32.7%) of them were labourers. The family monthly income was between Rs. 5000 and 10,000 for 70% of them. Only one person was unmarried.

The first objective of the study was to assess the risk factors of osteoporosis in the rural pre-menopausal women. As per the non-modifiable risk factors, the age and sex, all study participants were at risk of osteoporosis, as they were all women in the age group of 40–50. It is well established that major proportion of Indian women between the ages of 30 and 60 have various stages of osteoporosis.[8],[14],[15] It is also known that low BMI is associated with increased risk of osteoporosis.[16] In this study, only 12.72% were underweight which denoted that the number at risk for osteoporosis in the study group was less as per this modifiable risk factor. The other risk factors that were examined in this study included calorie and calcium intake and physical activity. Majority (85.64%) of women took 1000–1900 kcal/day and 45.45% of women had calcium intake of 310–400 mg/day [Table 1]. The mean calorie and calcium intake by the women were 1630.81 kcal/day and 310 mg/day which was much less than the daily requirement of a minimum 1900 calories and 600 g of calcium. Calcium supplements were not consumed by 77.27% of the study participants. The Indian Council of Medical Research has projected that many Indian women's diet do not meet the daily calcium requirement of 600 mgs of calcium[17] which is also proved to be true in this study participants. Low calcium intake is a major risk factor for low bone mineral density in pre-menopausal women leading to osteoporosis.[18] Therefore, it is suggested that the women in this study are at risk of osteoporosis. The study findings also showed some women (29.41%) were taking a calcium supplement which was not accounted for in the total calcium intake. This can have implications for the study. Although women in this study had low calorie intake, with respect to their BMI most were in the overweight (10%), obese I (43.64%) or obese II (11.82%) category. Poor nutrition leading to low body weight is an important risk factor for osteoporosis. However, in this study, their calorie intake was low, but the BMI of most women was high. Positive correlation has been found between BMI and BMD which gives a positive connotation for the study group women.
Table 1: Distribution of pre.menopausal women based on body mass index and intake of calorie and calcium

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With regard to physical activity, it was found that all the participants were involved in domestic and garden-related activities, but only 30% of women were involved in job-related physical activity. Studies conducted by Prince et al.[19] showed that the addition of an exercise regimen incorporating weight-bearing exercises was necessary to achieve beneficial effects of calcium supplementation on femoral neck BMD in young post-menopausal women. In a meta-analysis of 17 exercise trials, Specker[20] concluded that the beneficial effects of exercise on bone mass were only realised if calcium consumption was high, suggesting a synergistic action of calcium and exercise. Although the women in the study had inadequate calcium intake, their physical activity levels were quite high which may contribute to differing consequences. Sociocultural factors related to food intake, activity and exercise may also have to be explored.

In the current study, using FRAX® algorithms, the 10-year probability of fracture was predicted based on selected clinical factors. [Figure 1] shows distribution of pre-menopausal women based on 10-year probability of major osteoporotic fractures. Majority (92.73%) of the women had only 1%–2% of 10-year probability of major osteoporotic fracture risk and 95.45% had <0.5% of 10-year probability of major hip fracture risk, as per the risk factors such as previous fracture, family history of fracture, intake of glucocorticoids and BMI [Figure 1]. This study finding reveals that only 3 (2.73%) women had previous history of fracture. Family history of fracture was positive for 2 (1.82%) and only 2 (1.82%) were on glucocorticoids. The normal or high BMI in most women in this study and minimal presence of other risk factors might have contributed to the low 10-year probability of osteoporotic fracture risk.
Figure 1: Distribution of pre-menopausal women based on 10-year probability of major osteoporotic fracture and major hip fracture.

Click here to view

The second objective was to assess the knowledge of pre-menopausal women regarding osteoporosis [Figure 2]. The present study identified that 30.91% of women had poor knowledge, 49.09% had fair knowledge, 17.27% had good knowledge and 2.73% had very good knowledge. Furthermore, the present study revealed that 11.82% knew the correct meaning and definition of osteoporosis and 40.91% knew that deficiency of calcium causes osteoporosis. Osteoporosis is largely preventable and so is the fragility fractures caused by osteoporosis[21] and adequate knowledge on causes and risk factors of osteoporosis will in turn facilitate prevention of osteoporosis. Inadequate knowledge about osteoporosis on the other hand has been found to be a vital defining factor in prevention of osteoporosis and osteoporosis-related fracture.[22]
Figure 2:Distribution of pre-menopausal women based on knowledge regarding osteoporosis.

Click here to view

Similar study finding on knowledge of osteoporosis was noted by Von Hurst and Wham in New Zealand among 622 women with a mean total score of 16.4 out of 26 correct responses. Conflicting results were identified in a study conducted by Ayesha et al.[23] in Western India, revealed that majority (54%) were unaware of osteoporosis.

The third objective of the study was to determine the association between knowledge and selected demographic variables. There was a significant association of the knowledge of women regarding osteoporosis with their education (P< 0.01) and monthly family income (P< 0.01) [Table 2]. Similarly, in a cross-sectional study of post-menopausal Chinese women, it was found that a higher level of formal education, in particular tertiary education, was strongly associated with better bone mineral density values at various sites and with the lower prevalence of osteoporosis. The associations were present, even after adjustments for strong confounders such as age, years since menopause and body weight.[24] There was also a significant association of 10-year probability of major osteoporotic fracture risk with calcium supplements (P< 0.01) in this study. This is similar to findings of the study titled 'The efficacy of calcium supplementation alone in elderly Thai women over a 2-year period: a randomised controlled trial' where it was identified supplementation with elemental calcium 500 mg/day was helpful to decrease bone turnover and is effective in retarding bone loss at lumbar spine and slowing bone loss at femoral neck in elderly Thai women who had low dietary calcium intake.[25]
Table 2: Association of knowledge of pre-menopausal women regarding osteoporosis with demographic variables

Click here to view

The current study also revealed a significant association of 10-year probability of hip fracture risk with occupation (P< 0.01), which was low in the study group. Physical activity plays an important role in the development and maintenance of BMD, particularly those activities which involve weight-bearing and muscle loading. Bone growth and peak bone mass are enhanced by physical exercise and regular leisure-time exercise has been shown to retard bone loss in post-menopausal women.[26] Contrary to the present study findings, a study conducted by Haris, Jahan and Afreen[27] showed that occupation had a positive association with low bone mineral density.


The major limitation of the study was the inability to assess the bone mass density and confirm osteoporosis by bone scans. Another limitation was that the study was done in population drawn from one specific village and may not represent the total population of women in that age group in the state or country.

  Conclusion Top

Prevention is the most cost-effective means of managing osteoporosis. Beyond the limitations, the study has given some important insights into risk factors for osteoporosis in pre-menopausal women. Nurses, whether in hospital setting or in community need to take interest in prevention of osteoporosis, as the study showed that women lack knowledge regarding osteoporosis. It is important to understand the various factors that influence the health of an individual. Knowledge can influence health-related behaviour when mediated by attitudes and beliefs. An assessment of risk factors and existing knowledge regarding osteoporosis helps the nurse to focus on specific aspects in the prevention of osteoporosis. The nurse should be able to take the vital step in creating public awareness regarding prevention of osteoporosis. Effective individual strategies can be prescribed and promoted to enhance a healthy lifestyle. Thus, a nurse can help in building a healthy population with strong bones.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

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  [Table 1], [Table 2]


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