Declining bone mass in men with chronic pulmonary disease: contribution of glucocorticoid treatment, body mass index, and gonadal function

Vitamin D and bone health in adults with cystic fibrosis

BACKGROUND

Cystic fibrosis (CF) patients have chronic pancreatic insufficiency leading to malabsorption of fat-soluble vitamins, including vitamin D which can contribute to poor skeletal health and respiratory function.

OBJECTIVE

This study evaluated the prevalence of vitamin D insufficiency and its impact on bone and respiratory health in adults with CF.

DESIGN AND MEASUREMENTS

This was a retrospective study in which data were collected from medical records over a 2-year period. Data included patient demographics, lung function, biochemical data, bone mineral densities, X-rays and ascertainment of use of vitamin supplements. Data were collected from medical records at a single accredited CF Center. Serum 25-hydroxyvitamin D [25(OH)D] levels and bone mineral density studies were also collected.

PATIENTS

A total of 185 adults with CF were identified with a mean age of 29 +/- 9 years.

RESULTS

The prevalence of vitamin D insufficiency [25(OH)D < 75 nmol/l] was 76%. Mean serum 25(OH)D concentrations were 58.8 +/- 30 nmol/l. Use of specific vitamin D supplementation was protective against vitamin D insufficiency whereas use of multivitamins was not. There was a small, but significant, positive association between serum 25(OH)D and FEV(1) per cent predicted after controlling for age, gender, BMI and race (R(2) = 0.30, P < 0.001). A high prevalence (27%) of vertebral fractures was detected on lateral chest X-ray.

CONCLUSIONS

The prevalence of vitamin D insufficiency and poor skeletal health is high in the US CF population. Vitamin D status appears to be positively associated with lung function. Prospective studies to examine the impact of correction of vitamin D insufficiency on skeletal and lung health in adult CF are warranted.

Comorbidities in chronic obstructive pulmonary disease

Comorbidities such as cardiac disease, diabetes mellitus, hypertension, osteoporosis, and psychological disorders are commonly reported in patients with chronic obstructive pulmonary disease (COPD) but with great variability in reported prevalence. Tobacco smoking is a risk factor for many of these comorbidities as well as for COPD, making it difficult to draw conclusions about the relationship between COPD and these comorbidities. However, recent large epidemiologic studies have confirmed the independent detrimental effects of these comorbidities on patients with COPD. On the other hand, many of these comorbidities are now considered to be part of the commonly prevalent nonpulmonary sequelae of COPD that are relevant not only to the understanding of the real burden of COPD but also to the development of effective management strategies.

Relationship between pulmonary emphysema and osteoporosis assessed by CT in patients with COPD

BACKGROUND

Osteoporosis is one of the important systemic features of COPD. Although COPD itself is regarded as one risk factor for osteoporosis, the relationship between the extent of emphysema and reduced bone density is still unclear. Our first aim was therefore to measure vertebral bone density and the percentage of low-attenuation area (LAA%) in the lungs using chest CT scans in COPD patients. Our second aim was to investigate the relationships among CT scan measurements, anthropometric parameters, and pulmonary function.

METHODS

Chest CT scans and pulmonary function tests were performed in 65 male patients with COPD. Using CT images, the CT scan density of the thoracic and lumbar vertebrae (T4, T7, T10, and L1) and the LAA% were measured quantitatively, and their correlations were analyzed.

RESULTS

Linear regression analyses revealed that LAA% had a significant negative correlation with bone mineral density (BMD) [r = -0.522]. In addition, multiple regression analysis showed that only LAA% and body mass index (BMI) were predictive of BMD among age, BMI, smoking index, FEV(1), arterial blood gas, and LAA%.

CONCLUSIONS

The extent of pulmonary emphysema significantly correlated with reduced bone density. Our study suggested that COPD itself could be a risk factor for osteoporosis and that chest CT scanning is useful for the management of COPD as a systemic disease.

Osteoporosis in chronic obstructive pulmonary disease patients

PURPOSE OF REVIEW

The purpose of this review is to examine the state of knowledge and clinical practice in the association of chronic obstructive pulmonary disease to osteoporosis and fracture incidence.

RECENT FINDINGS

There is a clear association between chronic obstructive pulmonary disease and excessive bone loss/risk of fractures. Little is known about the pathophysiological processes involved in the bone loss, but recent reports point to a continuous systemic inflammatory state in patients with chronic obstructive pulmonary disease. This inflammation involves the release of inflammatory cytokines such as tumour necrosis factor-alpha and interleukin-1. During the course of chronic obstructive pulmonary disease, a protein catabolic process takes place, including increased production of catalytic enzymes (matrix metalloproteinases etc.), which together with the inflammatory cytokines induces bone resorption.

SUMMARY

Patients with chronic obstructive pulmonary disease are at increased risk of osteoporosis and fractures. Risk factors such as smoking, advanced age, physical inactivity, malnutrition, and low weight may be responsible, but a number of pathophysiological explanations including the presence of a chronic inflammatory state with increased levels of proinflammatory cytokines and protein catalytic enzymes may also be involved. The use of oral glucocorticoids is also a significant risk factor. Increased awareness is highly warranted to diagnose osteoporosis at an early stage, and professionals should be aware of the risk of osteoporosis in this patient population.

BMI and low bone mass in an elderly male nursing home population

Introduction:

Little is known about osteoporosis in institutionalized older adults. Risk factors such as low body mass index (BMI) have been investigated in female populations, but remain understudied in men. The objective of this study was to examine characteristics of older men residing in a nursing home who received bone mineral density evaluations.

Methods:

57 male Miami Veterans Affairs Medical Center (VAMC) nursing home residents were screened for osteoporosis using a peripheral dual X-ray (pDXA) technique. T-scores were categorized into three groups: normal (0>–1); osteopenic (−1 to −2.49); osteoporotic (<–2.5).

Results:

Average age was 76.2 years (standard deviation = 11.5; range: 48–100). T-scores indicated that 37.3% of the population was normal, 35.6% osteopenic, and 27.1% osteoporotic. 35.6% of patients had normal BMIs, 3.4% were underweight, 47.5% were overweight, and 13.6% were considered obese. There was a high prevalence of overweight and obese individuals (61.1%) in the osteopenic and osteoporotic groups.

Conclusion:

As expected, there was a high prevalence of low bone mass in our population (62%). However, overweight and obese men were more likely to have osteoporosis and osteopenia, contrary to literature and clinical knowledge. This finding may be partially explained by the prevalence of sedentary lifestyle and relative lack of weight-bearing activity in this group of men.

Validation of a novel risk estimation tool for predicting low bone density in Caucasian and African American men veterans

Osteoporosis in men is a frequently missed diagnosis. We developed an additive risk index, Mscore (male, "simple calculated osteoporosis risk estimation"), based on bone mineral density (BMD) at the femoral neck (FN) in 639 ambulatory older male veterans. Mscore was derived from the nearest whole number ratio among regression coefficients for 5 variables independently associated with osteoporosis. Mscore=[2 x (patient age in decades)-(weight in lb/10)+4 if gastrectomy, +4 if emphysema, +3 if two or more prior fractures+14]. Age and weight variable scores are truncated to integers (i.e., 7 if 75 yr, 18 if 185 lb). Increased risk is reflected in higher Mscore values. We validated Mscore in 197 Caucasian male patients (mean age, 69 yr): values of 9 or higher had 88% sensitivity, 57% specificity, and an area under the curve (AUC) of 0.84 for predicting osteoporosis at the FN (population prevalence, 11%). Mscore values ranged from -9 to 20 allowing us to define low (<9), moderate (9-13), or high (>13) risk categories. Two percent of low-risk men had osteoporosis, 36% or 55% of high-risk men had osteoporosis or osteopenia, respectively. In younger African American (n=134) male veterans (mean age, 61 yr), age and weight were the only variables independently predictive of FN BMD. A reduced Mscore(age-weight) (age and weight variable scores+14) at a cutoff threshold of 9 predicted osteoporosis in African American men (population prevalence, 3%) with a sensitivity of 100%, a specificity of 73%, and an AUC of 0.99. Finally, we compared Mscore with another validated osteoporosis self-assessment tool (OST). OST at a cutoff threshold of 4 or Mscore(age-weight) at a cutoff threshold of 9 performed similarly in both of our populations of Caucasian and African American men. In conclusion, a validated Mscore index with 5 variables was only slightly more robust for predicting osteoporosis in older Caucasian men than 2 (independently derived) risk indices based on age and weight. Mscore(age-weight) or OST is easy to use and can be applied in populations of younger African American men.

Low bone mineral density is related to severity of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) appears to be associated with low bone mineral density (BMD). BMD loss can be accelerated by a number of factors associated with COPD, but it is not known whether COPD itself has a direct effect. Our aim was to investigate in a cross-sectional study whether COPD patients have lower BMD than healthy individuals, and whether the severity of the disease affects BMD. Eighty-eight COPD patients attending a rehabilitation program were classified into stages II, III and IV using GOLD criteria. BMD was measured by dual X-ray absorptiometry in lumbar spine (L2-4), femoral neck (FN) and total body (TB). Values were converted to Z-scores (adjusted for age and sex). Associations between Z-scores and steroid use, body mass index, pack-years and six-min walking distance were analyzed. The Z-scores (mean and (CI)) for all patients were for L2-4: -0.6 (-0.9, -0.3), FN: -0.8 (-1.0, -0.5) and TB: -0.5 (-0.8, -0.2). All scores were significantly different from those of a control population (p<0.001). For all three variables (ZL2-4, ZFN, ZTB) there were significant differences between the stages. The difference for ZL2-4 was still significant after adjustment for risk factors. We conclude that BMD is low in COPD patients and decreases with increasing severity of the disease. Low BMD may to some extent be a disease-specific effect.

Is there an optimal corticosteroid regimen for the management of an acute exacerbation of chronic obstructive pulmonary disease?

Systemic corticosteroids are standard of care for the management of an acute exacerbation of chronic obstructive pulmonary disease (COPD). Several prospective, randomized trials demonstrated modest improvements in patient outcomes when short courses of systemic corticosteroids were used. However, the most appropriate dosage regimen remains controversial, as the corticosteroid regimens used in these trials differed greatly, and no studies have directly compared medium-, high-, and low-dose regimens. In addition, data are lacking on the safety, efficacy, and appropriate dosing of systemic corticosteroids in women and in patients with an acute exacerbation of COPD and concomitant pneumonia or severe respiratory failure. Systemic corticosteroid use is associated with several adverse effects that are dose and/or duration dependent. Evidence suggests that higher dose corticosteroid regimens may place patients at increased short-term and long-term risk, without additional clinical benefit. Tapering of systemic corticosteroid regimens, although a common practice, is unnecessary in most circumstances. The risk for hypothalamic-pituitary-adrenal-axis suppression is negligible when low-dose, short-course corticosteroid regimens are used, and no evidence exists to suggest that abruptly stopping a low-dose steroid regimen will increase the risk of disease relapse. Still, no studies have directly compared tapered and non-tapered regimens in patients with an acute exacerbation of COPD. Consistent with clinical guideline recommendations, safety and efficacy data support the use of low-dose corticosteroid regimens such as prednisone 40 mg orally once/day for 10-14 days in most patients with an acute exacerbation of COPD. Further studies are needed to clarify the optimal systemic corticosteroid regimen for an acute exacerbation of COPD.

Calcitriol does not prevent bone loss in patients with asthma receiving corticosteroid therapy: a double-blind placebo-controlled trial

INTRODUCTION

Oral glucocorticoid therapy reduces bone mineral density (BMD) and increases fracture risk. It is uncertain whether inhaled glucocorticoids, the most commonly used long-term therapy for asthma, have a similar effect. If bone loss does occur, it is unclear whether this is preventable by calcitriol. Patients with asthma receiving inhalational plus intermittent oral glucocorticoids lose bone, and treatment with 0.5 microg/day of calcitriol will prevent bone loss.

METHODS

A 2-year randomized double-blind placebo-controlled trial. One hundred eight patients with asthma were stratified by gender, age, and inhaled glucocorticoid dose and treated with calcitriol (n=55) or placebo (n=53). There were 41 men (mean age 53.2+/-1.7 years) and 67 women (mean age 49.1+/-1 years) with moderate to severe asthma (requiring >/=800 microg/day of beclomethasone dipropionate or equivalent maintenance therapy). BMD values at the lumbar spine (LS) and femoral neck (FN) were measured at baseline and at 6, 12, and 24 months using dual x-ray absorptiometry.

RESULTS

Changes in LS and FN BMD. Bone loss occurred in both groups at the FN (both p<0.03) and at the LS in the calcitriol (p<0.001), but not the control, group. Bone loss was not less in the calcitriol group at either site.

CONCLUSION

Patients with asthma receiving inhalational plus intermittent short courses of oral glucocorticoids lose bone. Calcitriol is unlikely to be appropriate therapy against this bone loss.

The prevalence of osteoporosis in patients with chronic obstructive pulmonary disease: a cross sectional study

Chronic obstructive pulmonary disease (COPD) is a complex disease, where the initial symptoms are often cough as a result of excessive mucus production and dyspnea. With disease progression several other symptoms may develop, and patients with moderate to severe COPD have often multiorganic disease with severely impaired respiratory dysfunction, decreased physical activity, right ventricular failure of the heart, and a decreased quality of life. In addition osteoporosis might develop possibly due to a number of factors related to the disease. We wanted to investigate the prevalence of osteoporosis in a population of patients with severe COPD as well as to correlate the use of glucocorticoid treatment to the occurrence of osteoporosis in this population. Outpatients from the respiratory unit with COPD, a history of forced expiratory volume in 1s (FEV1) less than 1.3 L, with FEV1% pred. ranging from 17.3% to 45.3% (mean 31.4%, standard deviation (sd) 7.3%). Patients between 50 and 70 years were included. Other causes of osteoporosis were excluded before inclusion. At study entry spirometry, X-ray of the spine (to evaluate presence of vertebral fractures), and bone mineral density of lumbar spine and hip were performed. Of 181 patients invited by mail, 62 patients were included (46 females and 16 males). All had symptoms of COPD such as exertional dyspnea, productive cough, limitations in physical activity etc. The mean FEV1 was 0.90 L (sd: 0.43 L) and the mean FEV1% pred. of 32.6% (sd: 14.1%). All had sufficient daily intake of calcium and vitamin D. In 15 patients, X-ray revealed compression fractures previously not diagnosed. Bone density measurements showed osteoporosis in 22 patients and osteopenia in 16. In total, 26 of the COPD patients were osteoporotic as evaluated from both X-ray and bone density determinations. Thus 68% of the participants had osteoporosis or osteopenia, but glucocorticoid use alone could not explain the increased prevalence of osteoporosis. A large fraction of these needed treatment for severe osteoporosis in order to prevent further bone loss and to reduce future risk of osteoporotic fractures. Thus, there is a significant need to screen patients with COPD to select the individuals in risk of fracture and to initiate prophylaxis or treatment for the disease.

Osteoporosis in diffuse parenchymal lung disease

STUDY OBJECTIVES

There are no studies focused on skeletal status in patients with diffuse parenchymal lung disease (DPLD). We hypothesized that patients with DPLD referred for lung transplantation would have a high prevalence of osteoporosis related to corticosteroid use or reduced pulmonary function and exercise capacity.

DESIGN

Retrospective cohort study.

SETTING

Tertiary care center.

PATIENTS

Eighty-six patients with DPLD referred to our center for lung transplantation evaluation between March 1999 and April 2004.

MEASUREMENTS AND RESULTS

Dual-energy X-ray absorptiometry was used to measure bone mineral density (BMD) at the lumbar spine, femoral neck, total hip, and radius at the time of referral. Criteria developed by the World Health Organization were used to define osteopenia and osteoporosis. Fifty-five patients (64%) had usual interstitial pneumonia-pattern lung disease, 14 patients (16%) had nonspecific interstitial pneumonia-pattern lung disease, and 17 patients (20%) had other forms of DPLD. Sixty-four patients (74%) were receiving corticosteroids, and 43 patients (50%) were receiving preventive therapy for osteoporosis. Eleven patients (13%; 95% confidence interval [CI], 7 to 22%) met criteria for osteoporosis at any site, and 49 patients (57%; 95% CI, 46 to 68%) had osteopenia. Lower body mass index (BMI) [adjusted odds ratio (OR), 1.3; 95% CI, 1.1 to 1.6; p = 0.007] and Hispanic ethnicity (adjusted OR, 9.7; 95% CI, 1.8 to 52; p = 0.008) were independently associated with an increased risk of osteoporosis. Linear regression analysis confirmed that BMD at the femoral neck and hip was directly associated with BMI (p < 0.002). These findings were not affected by adjustment for the use of corticosteroids or osteoporosis prophylaxis, pulmonary function, or exercise performance.

CONCLUSIONS

Reduced BMD was common in patients with DPLD who were referred for lung transplantation. Lower BMD was associated with lower BMI, whereas there was no association with other clinical factors in our cohort. Hispanic patients with DPLD had a higher risk of osteoporosis than non-Hispanic patients, independent of other variables. Given their increased risk of bone loss, patients with DPLD should undergo screening for osteoporosis and receive prophylaxis and treatment according to published guidelines.

Group training in patients with COPD - long-term effects after decreased training frequency

PURPOSE

To investigate effects of decreased training frequency in patients with COPD.

METHODS

Forty-three COPD patients participated in a controlled study. The intervention group (30 patients) trained 3 times a week during 3 months and once a week during 6 months. Before, after 3 and 9 months all patients performed walking tests, cycle ergometer tests and responded questionnaires on health-related quality of life (HRQoL) (SGRQ, SF-36).

RESULTS

At 9 months compared to 3 months there were no changes in distance walked in the groups. Both groups decreased their VO2peak and the training group deteriorated in HRQoL. At 9 months compared to baseline the training group showed increased distance walked compared to the control group. In the disease-specific SGRQ the training group tended to improve their activity score while the control group tended to deteriorate in total score. In SF-36 the control group decreased their physical component score.

CONCLUSION

Training once a week does not seem to be sufficient to maintain the level achieved after the 3-month period of training in COPD patients. However, training once a week during 6 months preceded by 3 months of high frequency training seems to prevent deterioration in physical capacity and HRQoL compared to baseline. Further studies are needed to investigate how to best sustain the benefits gained after physical training.

Reduced bone mineral density in male Severe Acute Respiratory Syndrome (SARS) patients in Hong Kong

During the Severe Acute Respiratory Syndrome (SARS) outbreak in Hong Kong in 2003, patients were treated with very high doses of corticosteroid and ribavirin. The detrimental effects of such treatment on the bone mineral density (BMD) of SARS patients are unknown. To compare the BMD of SARS patients with normal range data, a cross-sectional survey was conducted. The bone mineral density of 224 patients with SARS, who were treated with an average of 2753 mg (SD = 2152 mg) prednisolone and 29,344 mg (SD = 15,849 mg) of ribavirin was compared to normal data. Six percent of men had a hip BMD Z score of < or =-2 (P = 0.057 for testing the hypothesis that >2.5% of subjects should have a Z score of < or =-2). Moreover, there was a negative association (r = -0.25, P = 0.023) between the duration of steroid therapy and BMD in men. We conclude that male SARS patients had lower BMD at the hip than normal controls, and this could be attributed to prolonged steroid therapy.

Bone Mineral Density Improvement After Lung Volume Reduction Surgery for Severe Emphysema

BACKGROUND

In patients with severe emphysema, bone mineral density (BMD) is reduced and the risk of osteoporosis is increased.

STUDY OBJECTIVES

To identify the impact of lung volume reduction surgery on BMD.

DESIGN

Prospective cohort study.

SETTING

University hospital.

PATIENTS AND INTERVENTIONS

Forty emphysematous patients, all receiving oral steroid therapy, underwent bilateral lung volume reduction surgery. Thirty similar patients, who refused the operation, followed a standard respiratory rehabilitation program.

MEASUREMENTS

All subjects were evaluated pretreatment and 12 months posttreatment for respiratory function, nutritional status, and bone-related biochemical parameters. BMD was assessed by dual-energy radiograph absorptiometry.

RESULTS

After surgery, we observed significant improvements in respiratory function (FEV1, + 18.8% [p < 0.01]; residual volume [RV], -29.6% [p < 0.001]; diffusing capacity of the lung for carbon monoxide [Dlco], + 21.6% [p < 0.01]) nutritional parameters (fat-free mass, + 6.0% [p < 0.01]), levels of bone-related hormones (free-testosterone, + 20.5% [p < 0.01]; parathormone, -11.2% [p < 0.01]), bone turnover markers (osteocalcin, -12.7% [p < 0.05]; bone-alkaline-phosphatase, -14.0% [p < 0.05]; beta-crosslaps, -33.6% [p < 0.001]), BMD (lumbar, + 8.8% [p < 0.01]; femoral, + 5.5% [p < 0.01]), and T-score (lumbar, + 21.0% [p < 0.01]; femoral, + 12.4% [p < 0.01]) with reduction in osteoporosis rate (50 to 25%). Nineteen patients who had undergone surgery were able to discontinue treatment with oral steroids. These subjects showed a more significant improvement in BMD (lumbar, + 9.6%; femoral, + 6.8%; p < 0.001) and T-score (lumbar, + 27.3%; femoral, + 14.3%; p < 0.001). The remaining 21 patients who had undergone surgery experienced significant improvement compared to respiratory rehabilitation subjects despite continued therapy with oral steroids (BMD: lumbar, + 4.5% vs -0.7%, respectively [p < 0.01]; femoral, + 2.7% vs -1.1%, respectively [p < 0.05]; T-score: lumbar, + 14 vs -2.1, respectively [p < 0.01]; femoral, + 7.4 vs -2.7, respectively [p < 0.01]). The increase in lumbar BMD was correlated with the surgical reduction of RV (p = 0.02) and with the increase in Dlco (p = 0.01) and fat-free mass (p = 0.01).

CONCLUSIONS

Lung volume reduction surgery significantly improves BMD compared to respiratory rehabilitation therapy, even in patients requiring oral steroids. The increase in BMD correlates with RV, Dlco, and fat-free mass, suggesting that the restoration of respiratory dynamics, gas exchange, and nutritional status induces improvement in bone metabolism and mineral content.

Association between respiratory function and osteoporosis in pre- and postmenopausal women

OBJECTIVE

To investigate the relationships between respiratory function and osteoporosis, 132 premenopausal and 98 postmenopausal women were evaluated.

METHODS

Bone mineral density (BMD) was measured with dual-energy X-ray absorptiometry. Pulmonary function and anthropometric parameters were measured using a spirometer and a body composition analyzer.

RESULTS

Lumbar spine and proximal femur BMDs in postmenopausal women with forced expiratory volume in 1s (FEV1) > or = 92.0% averaged 0.83 +/- 0.12 g/cm2 and 0.67 +/- 0.11 g/cm2, which were significantly above the values (0.76 +/- 0.14 g/cm2 and 0.61 +/- 0.12 g/cm2, P < 0.05) in those with FEV1 <92.0%. The prevalences of osteoporosis at lumbar spine and proximal femur were 59.2 and 46.9% in the postmenopausal women with peak expiratory flow rate (PEFR) <5.12 l/s, significantly higher than those of osteoporosis at the corresponding sites in the women with > or = 5.12 l/s (36.7 and 20.4%, P < 0.05). Lumbar spine and proximal femur BMDs were positively correlated with FEV1 (r = 0.28, P < 0.05; r = 0.31, P < 0.05) and PEFR (r = 0.35, P < 0.05; r = 0.23, P < 0.05) in postmenopausal women; however, no significant correlations were observed in premenopausal women.

CONCLUSION

Pulmonary function seems to be more closely associated with BMD in postmenopausal women than in premenopausal women. Poor respiratory function may be an indicator of postmenopausal women at increased risk of osteoporosis.

The risk of nonvertebral fracture related to inhaled corticosteroid exposure among adults with chronic respiratory disease

OBJECTIVE

To examine nonvertebral fracture risk in relation to inhaled corticosteroid (ICS) exposure among adults with respiratory disease.

DESIGN AND PATIENTS

Nested case-control study within a cohort of 89,877 UnitedHealthcare members aged > or = 40 years with physician insurance claims for COPD or asthma, enrolled for > or = 1 year from January 1, 1997 to June 30, 2001.

METHODS

Cases (n = 1,722) represented patients with a first treated nonvertebral fracture (the index date is the first fracture claim). Control subjects (n = 17,220) were randomly selected from the person-time and assigned a random index date. ICS exposure was ascertained 1 month, 3 months, 6 months, and 12 months before the index date, with estimated cumulative dose through 0 to 6 months, 7 to 12 months, and 0 to 12 months. Covariates included demographics, oral corticosteroid and other medication exposure, comorbidities, and indicators of respiratory disease severity. Odds ratios (ORs) adjusted for all covariates were estimated by logistic regression.

RESULTS

No increased fracture risk with ICS exposure as a class or with fluticasone propionate alone was detected. ORs for exposure in the preceding 30 days were 1.05 (95% confidence interval [CI], 0.89 to 1.24), 1.13 (95% CI, 0.90 to 1.40), and 0.97 (95% CI, 0.78 to 1.21) for all ICS, fluticasone propionate, and other ICS, respectively. No dose-response effect was present. Among patients with COPD only (n = 6,932), no increased risk was found for recent ICS exposure (OR, 0.86; 95% CI, 0.59 to 1.25).

CONCLUSIONS

Concern about nonvertebral fracture risk should not strongly influence the decision to use recommended doses of ICS for adult patients with asthma or COPD in managed-care settings in the United States. This study could not evaluate very-high ICS dose, long-term ICS exposure, or vertebral fracture risk.

Associated loss of fat-free mass and bone mineral density in chronic obstructive pulmonary disease

We hypothesized that in patients with chronic obstructive pulmonary disease, loss of fat-free mass (FFM) and loss of bone mineral density (BMD) were related to (1) each other and may be clinically inapparent, (2) urinary markers of cellular and bone collagen protein breakdown, and (3) severity of lung disease. Eight-one patients and 38 healthy subjects underwent dual-energy X-ray absorptiometry to determine body composition and BMD. Urinary protein breakdown markers, inflammatory mediators, and their soluble receptors were determined. Thirty-three patients had a low fat-free mass index (kg/m(2)), 17 of whom had a normal body mass index. Thirty-two percent of patients (13% of healthy subjects) had osteoporosis at the hip or lumbar spine. The marker of cellular protein breakdown was elevated in patients and related to lung disease severity and body composition. The marker of bone collagen breakdown was greater in patients with osteoporosis. Inflammatory mediators were elevated in patients. Loss of FFM and loss of BMD were related, occurred commonly, and could be subclinical in patients with chronic obstructive pulmonary disease. Loss of both was greatest with severe lung disease. Increased excretion of cellular and bone collagen protein breakdown products in those with low FFM and BMD indicates a protein catabolic state in these patients.

Recognizing and treating glucocorticoid-induced osteoporosis in patients with pulmonary diseases

Glucocorticoids are frequently used to treat patients with pulmonary diseases, but continuous long-term use of glucocorticoids may lead to significant bone loss and an increased risk of fragility fractures. Patients with certain lung diseases, regardless of pharmacotherapy-particularly COPD and cystic fibrosis-and patients waiting for lung transplantation are also at increased risk of osteoporosis. Fragility fractures, especially of the hip, will have substantial effects on the health and well-being of older patients. Vertebral collapse and kyphosis secondary to glucocorticoid-induced osteoporosis (GIO) may affect lung function. Identification of patients with osteopenia, osteoporosis, or fragility fractures related to osteoporosis is strongly recommended and should lead to appropriate treatment. Prevention of GIO in patients receiving continuous oral glucocorticoids is also recommended. In patients receiving either high-dose inhaled glucocorticoids or low- to medium-dose inhaled glucocorticoids with frequent courses of oral glucocorticoids, bone mineral density measurements should be performed to screen for osteopenia and osteoporosis. A bisphosphonate (risedronate or alendronate), calcium and vitamin D supplementation, and lifestyle modifications are recommended for the prevention and treatment of GIO.

Chronic obstructive pulmonary disease: are women more susceptible than men?

Current data show that women now suffer from COPD at least as commonly as men. They seem to be more predisposed to suffer the adverse respiratory consequences of tobacco smoking with the development of COPD at an earlier age and with a greater degree of lung function impairment for a given amount of tobacco exposure. This may be explained, in part, by women's greater airway responsiveness to exogenous stimuli--an increased responsiveness that is explained largely by differences in lung size and geometry. Hormonal factors and immunologic factors that influence the lung also may differ between the sexes but their significance is poorly understood. Despite the increasing prevalence of COPD among women, their disease is more likely to be overlooked as compared with the same disease in men. This gender bias in diagnosis is not likely to be remedied until physicians begin to use spirometric testing to screen for this common disease. Women who smoke may have greater difficulty quitting than men. There are documented differences in health care use between men and women who have COPD, but too few studies have been done to allow conclusions to be drawn about the impact of sex and gender on the prognosis of the disease.

Vitamin D deficiency, bone mineral density and weight in patients with advanced pulmonary disease

OBJECTIVE

To study the influence of underweight, body composition and vitamin D deficiency on bone mineral density in patients with advanced pulmonary disease.

DESIGN

Cross-sectional study with time span for inclusion set at 5 years.

SETTING

The clinical work and biochemical analyses were carried out at Rikshospitalet University Hospital, Norway. Analyses for vitamin D metabolites and bone markers were carried out at Aker University Hospital, and bone measurements at Clinic of Osteoporosis.

SUBJECTS

Seventy-one candidates for lung transplantation (63% chronic obstructive pulmonary disease, 42 underweight and 29 normal weight) were included.

MAIN OUTCOME MEASURES

Body composition, bone mineral density at lumbar spine and femur neck, serum concentration of calcidiol and vitamin D intake.

RESULTS

Subnormal calcidiol levels were present in 52% of the underweight patients and 69% of the normal-weight patients. The resulting models of linear regression showed that for the lumbar spine T scores model, the total variation of 16.7% was explained by group (underweight/normal weight), sex and age. For the femur neck T scores model, the total variation of 20.4% was explained by the interaction of underweight and vitamin D deficiency (with borderline significance) and by arm muscle circumference percentage of standard. In patients with normal calcidiol levels, the median intake of vitamin D was 17 microg in the underweight patients and 11 microg in the normal-weight patients.

CONCLUSIONS

Vitamin D deficiency was common in both underweight and normal-weight patients, but only in the underweight patients, an association between vitamin D deficiency and reduced femur neck T scores was indicated.

Men's cardiovascular and pulmonary health

Heart disease in men is declining steadily, but it remains the number one killer of men in the United States. CLRD, influenza/pneumonia, and lung cancer are three more causes of top 10 mortalities in men. Epidemiological and clinical studies conclude that CVD is largely preventable through lifestyle modification. CHD, COPD, occupational lung disease, and lung cancer are all preventable by primary prevention (ie, no cigarette smoking). All men should be counseled about the grave significance of heart and lung disease as a cause of illness and death, the importance of primary prevention, and the great variability in symptom presentation. Nurses are in the ideal position to educate patients, families, and colleagues about heart and lung disease.

Secondary osteoporosis: underlying disease and the risk for glucocorticoid-induced osteoporosis

BACKGROUND

Chronic diseases of many organ systems require long-term (>or=1 year) treatment with glucocorticoids. Owing to the catabolic activity of glucocorticoid therapy, osteoporosis is a potential complication.

OBJECTIVES

This review discusses glucocorticoid-induced bone loss and the factors, including underlying disease, that increase the risk for osteoporosis. Therapeutic options for the prevention and treatment of glucocorticoid-induced osteoporosis (GIO) also are reviewed.

METHODS

A review of the English-language literature was conducted using the MEDLINE database and proceedings from scientific meetings. Search terms including glucocorticoid-induced osteoporosis, bone loss, and fracture were used to refine the search, and preference was given to studies published after 1990.

RESULTS

Long-term glucocorticoid treatment causes bone loss that is most precipitous in the first 6 months. Patients treated with glucocorticoids have additional risk factors for bone loss and osteoporosis that are associated with their primary disease. Chronic diseases can cause changes in bone metabolism, leading to bone loss in addition to that induced by glucocorticoids alone. Bone loss can be minimized through proper nutrition, weight-bearing exercise, calcium and vitamin D supplementation, and, where indicated, bisphosphonate treatment. The American College of Rheumatology Ad Hoc Committee on Glucocorticoid-Induced Osteoporosis guidelines recommend bisphosphonates for minimizing bone loss and fracture risk in patients at risk for GIO. Risedronate is indicated for the prevention and treatment of GIO, and alendronate is indicated for its treatment. Both risedronate and alendronate increase bone mineral density in patients at risk for GIO. Risedronate significantly reduces the incidence of vertebral fractures after 1 year of treatment (P<0.05). The effectiveness and tolerability of the bisphosphonates have not been established in pregnant women or pediatric patients.

CONCLUSIONS

Men and women initiating long-term glucocorticoid treatment and those with GIO should be concomitantly treated with effective osteoporosis therapy to reduce fracture risk and counseled on preventive lifestyle changes.

Fracture risk associated with inhaled corticosteroid use in chronic obstructive pulmonary disease

Patients with chronic obstructive pulmonary disease (COPD) are frequently treated with inhaled corticosteroids (ICS). However, the impact of ICS use on fracture risk remains unclear in these patients. This nested case-control study examines the association between ICS use and nonvertebral fractures in Veterans Affairs patients with COPD. From a cohort of 40,157 patients with a COPD diagnosis between October 1, 1998 and September 30, 1999, and that used services in the preceding 12-month period but did not have a COPD diagnosis, 1,708 cases with nonvertebral fractures were identified and matched to 6,817 control patients. Patients were 94% male, and average age was 62.7 years. ICS exposure was identified through prescription records and converted to beclamethasone equivalents. In conditional logistic regression models, exposure to ICS at any time during follow-up was not associated with an increased fracture risk (adjusted odds ratio = 0.97; 95% confidence interval, 0.84-1.11). However, current high-dose ICS users (> or = 700 microg per day) had an increased risk of fractures compared with patients with no exposure (adjusted odds ratio = 1.68; 95% confidence interval, 1.10-2.57). In patients with COPD, current use of high-dose ICS was associated with an increased risk of nonvertebral fractures.

Reversal of Chronic Obstructive Pulmonary Disease-Associated Weight Loss

Poor nutritional status is associated with an increased incidence of morbidity and mortality in patients with chronic obstructive pulmonary disease (COPD). While a number of factors have been shown to produce tissue catabolism, no single mechanism has been clearly identified as a primary cause for weight loss in patients with severe COPD. Without a clear understanding of the aetiology of weight loss, therapeutic strategies to reverse this process have historically been unsuccessful. A review of recent studies allows consideration of a model of mechanisms of weight loss. This model includes multiple pathways that may be activated singly or simultaneously to cause loss of weight, specifically lean body mass. These include energy imbalances, elevated levels of cytokines, tissue hypoxia and the effects of cocorticosteroid therapy. To date, interventional studies that have looked at newer pharmacotherapies such as growth hormone and anabolic steroids in patients with COPD who are losing weight have not demonstrated reversal of weight loss or improvement in nutritional status. Currently, early identification of patients at risk for weight loss and aggressive nutritional supplementation coupled with an exercise programme has demonstrated the greatest benefit. However, with increasing understanding of the mechanisms that may be implicated, new targets for therapies are being identified. Of particular research interest are molecules such as leukotrienes, hormones, tumour necrosis factor-alpha and acute-phase proteins, which are noted to be elevated in some patients with COPD-associated weight loss. Currently, inhibitors to some of these inflammatory substances are used therapeutically in other chronic illnesses such as rheumatoid arthritis and cancer cachexia. Future research may investigate their usefulness in COPD and direct new therapies that target the processes contributing to weight loss in these patients.

Cortical bone dynamics, strength, and densitometry after induction of emphysema in hamsters

Recent evidence suggests that patients suffering from chronic obstructive pulmonary disease are also at an increased risk of developing osteoporosis. The pathophysiological mechanism(s) linking these progressive diseases is unknown. The goal of this investigation was to determine whether there were alterations in bone mineral density and content, cortical bone structure and strength, and indexes of bone formation and resorption in the elastase-induced emphysematous hamster. At 3 wk after induction of emphysema, the femoral bone mineral content was 8% less (P = 0.026) and the femoral fracture strength was 6% less (P = 0.032) in the emphysematous hamster than in controls. The cortical area was 8.4% less (P = 0.013) and the periosteal mineral appositional rate was 27% less (P = 0.05) than in controls. Additionally, the endocortical eroded surface in the emphysematous group was about twice that in the control group (P = 0.003). Differences in some indexes of bone formation and resorption, paralleled by differences in bone structure and strength, were observed 3 wk after induction of emphysema. These differences in skeletal metabolism and strength may help explain some of the skeletal changes associated with chronic obstructive pulmonary disease in humans.

COPD in VA hospitals

The Department of Veterans Affairs (VA) Health Care System is the largest integrated single-payer system in the United States. Its primary mission is to provide primary care, specialized care, and related medical and social support services to veterans. Much time and resources are expended on chronic obstructive pulmonary disease, known as COPD, at VA hospitals and clinics, thereby justifying the development of multifaceted strategies to address this problem. This article discusses the special problems of COPD in veterans who use VA facilities. The article also highlights the contributions of the VA to the research, training, and development of clinical practice guidelines for the management of this pervasive disease and presents the challenges that threaten its role in this area.

Osteoporosis in pulmonary clinic patients: does point-of-care screening predict central dual-energy X-ray absorptiometry?

STUDY OBJECTIVES

Patients in a pulmonary clinic have disorders that predispose them to osteoporosis and may use glucocorticoid therapy, which has been associated with low bone mineral density (BMD) and increased fracture risk. Ideally, all patients at risk for osteoporosis would be screened using the best test available, which is central BMD by dual-energy x-ray absorptiometry (DXA). We proposed to stratify the risk for osteoporosis by the use of a simple questionnaire and point-of-care heel ultrasound BMD measurements.

DESIGN

Cross-sectional screening study.

SETTING

Pulmonary clinic in a single Veterans Affairs Medical Center.

PATIENTS

Approximately 200 male and female patients who had not had previous BMD testing were eligible for the study, and 107 gave consent.

INTERVENTIONS

One hundred seven men (white, 71 men; black, 35 men; and Asian, 1 man) underwent heel BMD testing and filled out a questionnaire. Ninety-eight men underwent a central DXA.

RESULTS

Of 98 subjects, 24.5% had a spine, total hip, or femoral neck (FN) T-score of <or= -2.5, which is the generally accepted definition of osteoporosis diagnosed using DXA, and 44.9% had a T-score of <or= -2.0. The best-fit models for predicting FN or total hip BMD included body weight, heel BMD, corticosteroid use for >or= 7 days, and race, which accounted for 52 to 57% of the variance. When a heel ultrasound T-score of -1.0 was tested to predict a central DXA T-score of -2.0, the sensitivity was 61% and the specificity 64%. Adding the questionnaire score and body mass index (BMI) to the heel T-score improved sensitivity but not specificity. Moreover, BMI and age predicted central BMD with similar sensitivity and specificity. Importantly, of 24 patients with a central DXA T-score of <or= -2.5, only 14 were identified by a heel T-score of <or= -1.0.

CONCLUSIONS

Although the findings from a heel ultrasound plus the answers to a questionnaire were reasonably good indicators for predicting the presence of low BMD, little predictability was gained over the use of BMI and age. In a group of pulmonary clinic patients, the prevalence of osteoporosis was clinically significant, and central DXA testing was the preferable technique for identifying patients who were at risk for fracture.

Glucocorticoid-induced osteoporosis

Therapeutic use of glucocorticoids can lead to many well-known adverse events. Of all potential serious side effects, glucocorticoid-induced osteoporosis (GIOP) is one of the most devastating complications of protracted glucocorticoid therapy in rheumatoid arthritis. GIOP is the most common form of drug-induced osteoporosis. Although much has been written about the association of glucocorticoids with bone disease among patients with chronic inflammatory conditions, many issues remain unsettled. This article focuses on areas of continued controversies, including the epidemiology and pathogenesis of GIOP, specification of a "safe" dose, methods for diagnosis of GIOP, and an evidence-based approach for GIOP prevention.

Glucocorticoid-induced osteoporosis in patients with sarcoidosis

BACKGROUND

Patients with sarcoidosis are at risk for osteoporosis caused by glucocorticoid therapy. However, because of potential hypercalciuria and hypercalcemia, the usual conservative treatment for low bone mass, calcium and vitamin D supplements, may not be well tolerated.

METHODS

Patients with sarcoidosis referred to a metabolic bone clinic were compared with other sarcoidosis patients studied prospectively and patients with chronic obstructive pulmonary disease (COPD) or asthma. The subjects underwent bone mineral density (BMD) testing, and the sarcoidosis patients underwent mobility testing and measurements of serum and urine chemistries, vitamin D levels, bone turnover markers, and sex hormone levels.

RESULTS

The subjects were mostly male African Americans in the 6th decade of life. Many took chronic oral glucocorticoid therapy and often used home oxygen therapy. Low hip BMD was common among the referred group, comparable with patients with COPD. Surprisingly, hypercalciuria and hypercalcemia were uncommon, and serum testosterone levels were frequently low. The use of calcium supplements, multivitamins containing vitamin D, and glucocorticoids had no impact on serum or urine calcium levels. From univariate analysis, potential risk factors for low hip BMD were low weight, low body mass index (BMI), advanced age, and current use of glucocorticoids. However, in stepwise multiple regression analysis, only low BMI predicted about 40% of hip BMD.

CONCLUSIONS

Despite calcium and vitamin D supplements, this group of patients with sarcoidosis had low BMD but relatively infrequent hypercalciuria and hypercalcemia. No prediction model of BMD was adequate. Therefore, we conclude that each patient needs to be assessed individually, including measurement of BMD, serum and urine calcium, and sex steroid status.

The risk of osteoporosis in Caucasian men and women with obstructive airways disease

PURPOSE

Because patients with obstructive airways disease may be susceptible to osteoporosis, we sought to determine the association between airflow obstruction and osteoporosis.

SUBJECTS AND METHODS

We analyzed data from Caucasian participants (n = 9502) in the Third National Health and Nutrition Examination Survey, conducted in the United States between 1988 and 1994. We used data from dual-energy x-ray absorptiometry measurements of the total femur to determine whether a study participant had osteoporosis (defined as total bone mineral density values < or =2.5 SD below the corresponding mean values from young, healthy participants). We calculated the odds ratio (OR) for osteoporosis in four lung function categories: none, mild, moderate, and severe airflow obstruction.

RESULTS

Overall, airflow obstruction was associated with increased odds of osteoporosis compared with without airflow obstruction (OR = 1.9; 95% confidence interval [CI]: 1.4 to 2.5). Participants with severe airflow obstruction were at especially increased risk (OR = 2.4; 95% CI: 1.3 to 4.4). Moderate but not mild airflow obstruction was also associated with osteoporosis.

CONCLUSION

Airflow obstruction was an important risk factor for osteoporosis in the study population. These data highlight the importance of measuring bone mineral density in those with moderate-to-severe airflow obstruction for the detection and prevention of osteoporosis-related morbidity.

A comparison of bone mineral density in elderly female patients with COPD and bronchial asthma

BACKGROUND

A recent study has shown that osteoporosis and vertebral fractures are quite common in patients with advanced COPD and showed a significant relationship to the mortality of these patients. These results suggested that management of osteoporosis in advanced COPD is an important intervention. But whether patients with COPD who had never received chronic systemic corticosteroids have a high incidence of osteoporosis and whether these patients require treatment strategies to decrease osteoporotic fracture is not yet known. Furthermore, it is unclear whether there are differences in terms of the degree of osteoporosis between patients with COPD and patients with bronchial asthma.

OBJECTIVES

To compare the degree of osteoporosis and bone metabolism markers between elderly women with COPD and those with bronchial asthma who had never received chronic systemic corticosteroids, and to determine the factors influencing bone metabolism in these patients.

DESIGN

Cross-sectional medical survey.

PATIENTS

A total of 44 elderly female patients with COPD (n = 20) or bronchial asthma (n = 24) who had not received chronic systemic corticosteroids were enrolled (mean +/- SEM age, 74.6 +/- 1.0 years).

MEASUREMENTS

Total body and lumbar bone mineral density (BMD) were measured by dual-energy x-ray absorptiometry, and the data were compared between the two groups. In addition, the association between bone mass and clinical variables was determined.

RESULTS

When lumbar BMD was expressed as a Z score, the Z scores of patients with COPD were significantly lower than those of patients with bronchial asthma (p < 0.01). The prevalence of osteoporosis was also significantly higher in patients with COPD (50% vs 21%, p < 0.05). In patients with COPD, body mass index was positively correlated with BMD in the lumbar spine (r = 0.55, p = 0.02) and total body (r = 0.49, p = 0.03). Other clinical, biochemical, and anthropometric variables were not correlated with BMD.

CONCLUSIONS

In elderly female patients, osteoporosis is more common in cases of COPD than in bronchial asthma, even if these patients had not received long-term systemic corticosteroids. The explanation for the higher prevalence of osteoporosis in COPD is still not known, but preventive strategies to decrease osteoporotic fractures should be added to the management of elderly patients with COPD.

Osteoporosis in men: pathophysiology, evaluation, and therapy

Osteoporosis is a serious health problem for men. An advance in our understanding of the pathophysiology and treatment of this disorder has resulted in the possibility of a gender-specific approach to screening, diagnosis, and treatment. Here we review the data on osteoporosis in men, discuss controversies regarding whom to screen, whom to treat, and how to treat. Recent treatment data as they relate to men are reviewed, and a clinical treatment algorithm is presented.

COPD and osteoporosis

Osteoporosis, with resulting fractures, is a significant problem in patients with advanced COPD. The etiology for the bone loss is diverse but includes smoking, vitamin D deficiency, low body mass index, hypogonadism, sedentary lifestyle, and use of glucocorticoids. Effective strategies to prevent bone loss and/or to treat osteoporosis include calcium and vitamin D, hormone replacement when indicated, calcitonin, and bisphosphonate administration. However, many patients remain undiagnosed until their first fracture because of the lack of recognition of the disease. With an increased awareness by pulmonologists and the increased use of preventive strategies, the impact of osteoporosis on those patients with COPD should decrease.

Effects of inhaled corticosteroid and short courses of oral corticosteroids on bone mineral density in asthmatic patients : a 4-year longitudinal study

BACKGROUND

It is not certain whether inhaled corticosteroid (ICS) therapy reduces bone mineral density (BMD) in asthmatic patients. In addition, the potential risk of osteoporosis associated with the rescue use of short courses of oral corticosteroids (SC-OCS) is unclear.

OBJECTIVE

To evaluate the effect of inhaled beclomethasone dipropionate (BDP) and SC-OCS on BMD in asthmatic patients.

DESIGN

A 4-year longitudinal study.

METHOD

Lumbar BMD was measured twice by dual-energy x-ray absorptiometry at a mean (+/- SD) interval of 4.2 +/- 0.1 years in 35 asthmatic adults (15 men and 20 postmenopausal women; mean age at the second evaluation, 60.6 +/- 11.5 years) who had been treated with BDP and SC-OCS.

RESULTS

The average period of BDP treatment was 7.7 +/- 2.2 years (range, 4.8 to 13.0 years) at the second evaluation. During the study period, the daily dose of BDP was 765 +/- 389 microg (range, 100 to 1,730 microg), and the frequency of SC-OCS was 1.9 +/- 2.7 courses per year (range, 0.0 to 8.9 courses per year). As a whole, lumbar BMD was unchanged during the course of the study, whereas the Z score (ie, the percentage of normal value predicted from age and sex) increased significantly. Changes in BMD and Z scores in patients receiving high doses of BDP (ie, > 1,000 microg/d; n = 9) were not significantly different from those of patients receiving lower doses (ie, <or= 1,000 microg/d; n = 26). However, patients receiving frequent SC-OCS (ie, > 2.5 courses per year; n = 9) showed a significantly greater loss in BMD and Z score compared with those receiving sporadic courses (ie, <or= 2.5 courses per year; n = 26) (p = 0.002 and p = 0.035, respectively).

CONCLUSIONS

ICS therapy per se does not affect BMD, whereas frequent SC-OCS may do so.

Extrapulmonary effects of chronic obstructive pulmonary disease

Although airflow obstruction is the most obvious and most studied manifestation of chronic obstructive pulmonary disease (COPD), it should not be overlooked that COPD, particularly in its later stages, is associated with many extrapulmonary features that contribute to the morbidity, reduced quality of life, and, possibly, mortality of this disease. We review here the literature on skeletal muscle dysfunction, osteoporosis, and weight loss in COPD, with particular attention to possible approaches to their management. Patients with COPD may also have other extrapulmonary effects such as hormonal abnormalities that could probably be corrected, but less is known about them. COPD, therefore, should be regarded as a systemic disorder. Its systemic manifestations should not be overlooked in the overall care of the patient, because there are important ways in which they can be addressed.

Correlates of osteoporosis in chronic obstructive pulmonary disease

The aim of this study was to analyse the correlates of reduced bone mineral density in patients with chronic obstructive pulmonary disease (COPD), with special regard to a possible protective role of hypercapnia. One hundred and four consecutive COPD inpatients in stabilized respiratory conditions underwent a comprehensive assessment of their health status. Bone mineral density was measured by X-ray absorptiometry at the lumbar site and at the femoral neck site. Differences in health-related variables between patients with (group O, n=62) and without (group N, n=42) lumbar and/or femoral neck osteoporosis were assessed first by univariate analysis and then by logistic regression analysis aimed to identify independent correlates of osteoporosis. Group O was characterized by worse nutritional status, as reflected by indices exploring either lean or fat mass, and by a trend towards lower forced expiratory volume in 1 sec/forced vital capacity ratio. Arterial tension of carbon dioxide lacked any correlation with bone mineral density. According to the logistic regression analysis, body mass index < or = 22 kg m(-2) qualified as the only and positive independent correlate of osteoporosis (odds ratio=4.18; 95% confidence intervals=1.19-14.71). In conclusion, malnutrition characterizes COPD patients with osteoporosis, while mild to moderate hypercapnia lacks either a positive or negative effect on bone mineral density. Longitudinal studies are needed to identify predictors rather than correlates of bone mineral density.