Understanding the interplay between factors that influence bone mineral density in CF

Abstract

Background and Objectives Multiple factors affect bone mineral density (BMD) in cystic fibrosis (CF). Our aim was to perform comprehensive analyses of parameters potentially contributing to BMD. Methods A prospective single‐center study assessing BMD, and correlations with multiple parameters including pancreatic status, lung functions, 6‐minute walk test (6MWT), clinical score (modified Shwachman‐Kulczycki [SK] score), vitamin D, nutritional intake, hand grip strength (HGS), habitual physical activity (smart watches), and quality of life (SF‐36 questionnaire). Results Forty CF patients, mean age 18.3 ± 8.1 years, forced expiratory volume in 1 second 74.7% ± 17.9% predicted. Fifteen (37.5%) and 11 (27.5%) had osteopenia and osteoporosis, respectively. BMD was similar in pancreatic sufficient (pancreatic sufficient [PS], n = 15) and insufficient (pancreatic insufficient [PI], n = 25); median hip z score −1.5 ((−2.7)−(+0.2)) vs −1.5 ((−3.5)−(+0.7)), P = .79; spine −0.8 ((−2.2)−(+2)) vs −1.2 ((−4.4)−(+1.5)), P = .39 in PS vs PI, respectively. BMD correlated with HGS (r = .72, P < .001 hip; r = .52, P = .001 spine) and fat‐free mass index (r = .81, P < .001 hip; r = .63, P < .001 spine). BMD z score correlated weakly with SK score and moderately with SF‐36 general health. Data from smart watches, nutrition questionnaires, and 6MWT did not correlate with BMD. In a multivariate model, age and SK score predicted spine z score BMD. Conclusions A substantial number of CF patients have low BMD. Similar rates in PS and PI suggest that other factors, such as disease severity, may contribute to low BMD. SK and age, which can easily be obtained even with limited resources, were the best predictors of low BMD. Further larger multicenter studies are warranted to evaluate the contribution of multifactorial etiologies to low BMD in CF.

Effect of Trikafta on bone density, body composition and exercise capacity in CF: A pilot study

“…19 Our group previously examined 40 CF patients and found that 15 (37.5%) and 11 (27.5%) had osteopenia and osteoporosis, respectively. 20 In our study, there was a significant increase in hip and spine BMD in the study group, while BMD remained stable in the control group.…”

Handgrip Strength: Associations with Clinical Variables, Body Composition, and Bone Mineral Density in Adults with Cystic Fibrosis

“…In their group, BMD was low in 78.2% of adults with CF, a figure higher than ours, which was associated with respiratory function, physical function (walking test and HGS), and nutritional status [10]. In addition, Gur et al observed correlations between BMD and HGS (both at hip and spine level), and FFM, in addition to a high percentage of osteoporosis (27.5%) and osteopenia (37.5%) in 40 CF patients with a mean age of 18 years [30]. In patients with non-CF bronchiectasis, we also found that respiratory parameters, body composition, muscle strength, and bone remodelling biomarkers were associated with a lower BMD [42].…”

“…A total of 53 CF patients were included in the study; 22 (41.5%) were male and 31 (58.5%) were female. Class I and II mutations for the CFTR gene were the most frequently found; for gene A, class I mutation was found in 15.4% [8], class II in 78.8% [30], class III in 1.9% [1], and class IV in 3.8% [2], while no class V mutations were found. For the B gene, the distribution of mutations was class I in 41.7% [20], class II in 39.6% [19], class III in 2.1% [1], class IV in 10.4% [5] and class V in 6.3% [3].…”

Year in Review 2020: Multisystemic Impact of Cystic Fibrosis

“…Multiple factors can contribute to low bone mineral density (BMD) in patients with CF. A prospective, single center study evaluated 40 patients (>age 7 years) with CF to help determine clinical factors likely to contribute to BMD 27 . Osteopenia was seen in 37.5% (15/40) and 27.5% (11/40) had osteoporosis, with no differences seen between PS or PI patients.…”