The association between low back pain and osteoarthritis of the hip and knee: a population-based cohort study.

OBJECTIVE: The purpose of this study was to determine whether prevalent self-reported back pain predicts future osteoarthritis-related pain and disability in individuals with hip and knee osteoarthritis (OA). METHODS: We studied a population-based cohort of Ontario residents who were 55 years or older and reported symptomatic hip/knee OA at baseline (between 1996 and 1998). The sample was followed-up between 2000 and 2001. We used multivariable linear regression to model the association between baseline back pain and pain and disability (Western Ontario and McMaster Universities Osteoarthritis Index scores) at follow-up while controlling for confounders. RESULTS: Of the 983 participants, 58% of the cohort reported low back pain at baseline. Baseline low back pain predicted higher hip and/or knee OA-related pain and disability at follow-up (beta = 2.49; 95% confidence interval [CI], 0.4-4.6; P = .023). However, this association varied with the location of OA. After controlling for confounders, the association was strong for individuals with hip OA (beta = 11.41; 95% CI, 5.1-17.7; P = .001). However, low back pain was not associated with pain and disability in individuals with knee OA (beta = 0; 95% CI -3.39 to 3.39; P = .998). CONCLUSIONS: In a cohort of individuals with OA of the hip or knee, we found that low back pain predicted subsequent OA-related pain and disability in those with hip disease, but not knee disease. Our study provides valuable prognostic information to clinicians involved in the management of patients with OA of the hip and knee.

A prospective study to identify factors affecting adherence to recommended daily calcium intake in women with low bone mineral density.

OBJECTIVE: Factors that influence calcium intake among women with low bone mass have not been clearly identified. The objective of this study was to evaluate confidence, attitudes and beliefs regarding calcium intake and to identify determinants of adherence to calcium recommendations among women with low bone mineral density (BMD). METHODS: Participants were 104 women with low BMD attending an initial visit to an osteoporosis program. Prior to participation in a one-on-one standardized nutrition counseling session with a dietitian, daily calcium intake was assessed using four-day food records and use of calcium supplements was reported. Calcium related knowledge and beliefs were assessed by questionnaire. Barriers and facilitators to obtaining adequate calcium intake were also reported. Six months following baseline, food records and study questionnaire were repeated. Adherence was defined as meeting > or =85% of recommended calcium intake. Logistic regression was used to examine baseline predictors of adherence to calcium recommendations at follow-up. RESULTS: Mean dietary calcium intake was 952 +/- 384 mg/day at follow-up and 91.3% were using calcium supplements. Combining dietary and supplemental calcium, approximately 77% of women were adherent to calcium recommendations at follow-up. Uncertainty regarding calcium food sources and supplements, concerns related to weight gain and the fat content of some calcium-rich foods were the most frequently reported barriers to obtaining adequate calcium intake. The only significant independent predictor of calcium adherence at follow-up was use of a calcium supplement (adjusted OR = 5.970, p = 0.012). CONCLUSIONS: Due to the nutrient synergy of foods, dietary sources of calcium should continue to be promoted in nutritional counseling efforts as the optimal method of obtaining adequate calcium. Nutrition education should emphasize strategies to decrease side effects associated with calcium-rich foods and alleviate concerns regarding the cholesterol and fat content of some calcium-rich foods. In addition to strategies to increase consumption of dietary sources of calcium, supplementation should be considered as an acceptable method of increasing calcium intake among women with low BMD.

Fatigue in osteoarthritis: a qualitative study.

BACKGROUND: Fatigue is recognized as a disabling symptom in many chronic conditions including rheumatic disorders such as rheumatoid arthritis (RA) and lupus. Fatigue in osteoarthritis (OA) is not routinely evaluated and has only been considered in a very limited number of studies. To date, these studies have focused primarily on patients with OA under rheumatological care, which represent the minority of people living with OA. The purpose of this study was to increase our understanding of the fatigue experience in community dwelling people with OA. METHODS: In 2004, 8 focus groups were conducted with 28 men and 18 women (mean age 72.3) with symptomatic hip or knee OA recruited from a population-based cohort. Participants completed a self-administered questionnaire, which included demographics, measures of OA severity (WOMAC), depression (CES-D) and fatigue (FACIT). Sessions were audio taped and transcribed verbatim. Two researchers independently reviewed the transcripts to identify themes. Findings were compared and consensus reached. RESULTS: Mean pain, disability, depression and fatigue scores were 8.7/20, 27.8/68, 15.4/60, and 30.9/52, respectively. Participants described their fatigue as exhaustion, being tired and "coming up against a brick wall". Participants generally perceived fatigue as different from sleepiness and distinguished physical from mental fatigue. Factors believed to increase fatigue included OA pain and pain medications, aging, various types of weather and poor sleep. Mental health was identified as both affecting fatigue and being affected by fatigue. Participants described fatigue as impacting physical function, and their ability to participate in social activities and to do household chores. Rest, exercise, and avoiding or getting assistance with activities were cited as ways of coping. Participants generally did not discuss their fatigue with anyone except their spouses. CONCLUSION: Participants with OA described experiencing notable amounts of fatigue and indicated that it had a substantial impact on their lives. Further research is required to better understand the role of fatigue in OA in order to identify strategies to reduce its impact.

Factors that influence adherence to calcium recommendations.

To identify barriers to following calcium recommendations among women with reduced bone mineral density (BMD), four focus group sessions were held with 30 postmenopausal women diagnosed with low BMD. Key concepts and themes were derived from transcripts. Participants were aware of the importance of calcium to their bone health, and were attempting to follow calcium intake recommendations. Several major themes associated with the ability to obtain adequate calcium were identified, including knowledge and confidence in actions, lifestyle and food preferences, and side effects and conflict with other health conditions. Participants reported that they obtained information in an effort to make a confident decision about calcium intake, but were easily confused by conflicting information. Daily routines and family and personal food preferences influenced dietary behaviours. Women indicated that side effects, particularly those associated with perceived lactose intolerance, caused them to restrict their calcium intake. Our data provide important insight into factors that women believe affect their ability to reach recommended calcium intakes. To optimize osteoporosis prevention and treatment, dietitians should focus on individualized patient assessments to identify factors affecting adherence to dietary calcium recommendations.

Folate intakes and awareness of folate to prevent neural tube defects: a survey of women living in Vancouver, Canada.

OBJECTIVE: To estimate folate intake and knowledge in women of childbearing age, in relation to risk of neural tube defects. SUBJECTS/SETTING: One hundred forty-eight women (aged 18 to 45 years) in the Vancouver area of British Columbia, Canada. DESIGN: Using an interviewer-administered survey, we examined women for folate knowledge and the relation of folate knowledge to intake in a random sample. Contribution of folate from food, fortified grain products, and supplements was assessed by validated semiquantitative food frequency questionnaire. STATISTICAL ANALYSIS PERFORMED: Descriptive statistics, t tests, Chi;(2), Pearson correlation analysis. RESULTS: Mean daily folate intake from food, fortified foods, and supplementation was 812+/-710 Dietary Folate Equivalents (DFE)/day. Fortification of bread and grain products contributed 104+/-68 microg synthetic folic acid (SFA)/day (equal to 174+/-114 DFE), and supplements contributed 205+/-388 microg SFA/day. Although 86% of women met the Estimated Average Requirement (320 DFE/day) for folate, only 26% met the recommendation (400 microg SFA/day) for women capable of becoming pregnant. Most (95%) of the women had heard of folate, but only 25% knew that it could prevent birth defects. One-fourth of the women had good or very good knowledge of folate-rich foods. However, folate knowledge was not related to its intake. The most common sources of folate information were magazines/newspapers, doctors, and television/radio. Lack of awareness of the importance of folate was the most common reason given for choosing not to use folic acid supplements before pregnancy. However, 78% of the women indicated that, with knowledge of the benefits of folate, they would use supplemental folic acid daily to reduce the risk of birth defects. APPLICATIONS/CONCLUSIONS: Educational strategies are required to increase folate awareness among women and to promote the benefits of periconceptional folic acid supplementation. Targeting physicians to educate women on the importance of folate could be a potentially successful route. J

A longitudinal study to explain the pain-depression link in older adults with osteoarthritis.

OBJECTIVE: To evaluate whether osteoarthritis (OA) pain determines depressed mood, taking into consideration fatigue and disability and controlling for other factors. METHODS: In a community cohort with hip/knee OA, telephone interviews assessed OA pain and disability (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]), fatigue (Multidimensional Fatigue Symptom Inventory), depressed mood (Center for Epidemiologic Studies Depression Scale), and covariates (demographics, self-rated health, comorbidity, pain coping, pain catastrophizing, and social support) at 3 time points over 2 years. Drawing on previous research, a path model was developed to test the interrelationships among the key concepts (pain, depression, fatigue, disability) over time, controlling for covariates. RESULTS: The baseline mean age was 75.4 years; 78.5% of the subjects were women, 37.2% were living alone, and 15.5% had ≥3 comorbid conditions. WOMAC scores indicated moderate OA symptoms and disability. From the final model with 529 subjects, adjusting for covariates, we found that current OA pain strongly predicted future fatigue and disability (both short and long term), that fatigue and disability in turn predicted future depressed mood, that depressed mood and fatigue were interrelated such that depressed mood exacerbated fatigue and vice versa, and that fatigue and disability, but not depressed mood, led to worsening of OA pain. CONCLUSION: Controlling for other factors, OA pain determined subsequent depressed mood through its effect on fatigue and disability. These effects led to worsening of pain and disability over time. These results support the need for improved pain management in OA to prevent or attenuate the downstream effects of pain on disability and mood.

The nerve of osteoarthritis pain.

OBJECTIVE: Cumulative data suggest that central sensitization may contribute to pain in osteoarthritis (OA) and present with symptoms typically associated with neuropathic pain (NP). We evaluated the responses from focus group participants on the knee OA pain experience for pain descriptions that suggest NP. METHODS: Focus group transcripts were analyzed by 2 independent assessors for unprompted use of pain descriptors that suggested NP. Items from validated NP symptom-based questionnaires were used to guide the analysis. Data on sociodemographic factors, duration of knee OA, and OA disease and pain severity (using the Western Ontario and McMaster Universities Osteoarthritis Index and a numerical rating scale) were obtained from questionnaires administered after focus group completion. These factors were compared among participants who did and did not use descriptors that suggested NP. RESULTS: Transcripts from 80 knee OA participants were analyzed. A range of NP descriptors was used to characterize their knee symptoms, including burning, tingling, numbness, and pins and needles. The proportion of participants who used NP descriptors was 0.34 (95% confidence interval 0.24-0.45). Those who used NP descriptors were younger (P = 0.003) and, although not statistically different, more likely to be women, with higher pain intensity and OA severity and longer OA duration, than those who did not use NP descriptors. CONCLUSION: During focus groups, a subset of adults with chronic, symptomatic knee OA used pain quality descriptors that were suggestive of NP. Elicitation of NP descriptors in people with OA may help identify those who could benefit from further evaluation and perhaps treatment for NP.

Validation of a phytoestrogen food frequency questionnaire with urinary concentrations of isoflavones and lignan metabolites in premenopausal women.

OBJECTIVE: The purpose of this study was to examine the association between dietary intake of phytoestrogens estimated by a food frequency questionnaire (FFQ) with urinary metabolites. METHODS: Participants were 26 premenopausal, Caucasian women aged 25 to 42 years. Dietary intake of isoflavones (genistein and daidzein) and lignans (secoisolariciresinol and matairesinol) were estimated by a 53-item interviewer-administered FFQ on two occasions, reflecting 'habitual' (previous 2 months) and 'recent' (previous 2 days) dietary intake. Isoflavone (genistein, daidzein) and lignan (enterolactone, enterodiol and secoisolariciresinol) concentrations were measured in 24-hour urine samples by gas chromatography-mass spectrometry. Correlations between FFQ (habitual and recent, separately) and urinary metabolite values were assessed using Spearman correlation coefficients. RESULTS: Mean habitual isoflavone and lignan intakes were 13.7 mg/day and 13.8 mg/day, respectively. Mean urinary concentrations of isoflavones and lignans were 17.4 micromol/day and 20.6 micromol/day, respectively. Recent and habitual isoflavone intakes were correlated with urinary excretion of metabolites (r = 0.64, p < 0.001 and r = 0.54, p = 0.004, respectively). Urinary excretion of lignans was also modestly correlated with recent and habitual lignan intakes (r = 0.46, p = 0.02 and r = 0.40, p = 0.05, respectively). CONCLUSIONS: Our results support the use of this FFQ as a measure of dietary isoflavone and lignan intake in epidemiological studies.