Assessment of gait and posture characteristics using a smartphone wearable system for persons with osteoporosis with and without falls.

We used smartphone technology to differentiate the gait characteristics of older adults with osteoporosis with falls from those without falls. We assessed gait mannerism and obtained activities of daily living (ADLs) with wearable sensor systems (smartphones and inertial measurement units [IMUs]) to identify fall-risk characteristics. We recruited 49 persons with osteoporosis: 14 who had a fall within a year before recruitment and 35 without falls. IMU sensor signals were sampled at 50 Hz using a customized smartphone app (Lockhart Monitor) attached at the pelvic region. Longitudinal data was collected using MoveMonitor+ (DynaPort) IMU over three consecutive days. Given the close association between serum calcium, albumin, PTH, Vitamin D, and musculoskeletal health, we compared these markers in individuals with history of falls as compared to nonfallers. For the biochemical parameters fall group had significantly lower calcium (P = 0.01*) and albumin (P = 0.05*) and higher parathyroid hormone levels (P = 0.002**) than nonfall group. In addition, persons with falls had higher sway area (P = 0.031*), lower dynamic stability (P < 0.001***), gait velocity (P = 0.012*), and were less able to perform ADLs (P = 0.002**). Thus, persons with osteoporosis with a history of falls can be differentiated by using dynamic real-time measurements that can be easily captured by a smartphone app, thus avoiding traditional postural sway and gait measures that require individuals to be tested in a laboratory setting.

Quantifying misdiagnosis rates from cross-calibration biases and precision errors in dual-energy X-ray absorptiometry of the femoral neck.

BACKGROUND: Dual-energy X-ray absorptiometry (DXA) is an exam that measures areal bone mineral density (aBMD) and is regularly used to diagnose and monitor osteoporosis. Except for exam quality issues such as operator error, the quantitative results of an exam are not modified by a radiologist or other physician. DXA cross-calibration errors can shift diagnoses, conceivably leading to alternate intervention decisions and patient outcomes. PURPOSE: After identifying and correcting a cross-calibration bias of 3.8% in our two DXA scanners' aBMD measurements, we investigated misdiagnosis rates for given cross-calibration errors in a single patient cohort to determine the impact on patient care and the value of cross-calibration quality control. METHODS: The studied cohort was 8012 patients of all ages and sexes with femoral neck exams that were scanned on a single DXA unit from October 1, 2018 to March 31, 2021. There were six subcohorts delineated by age and sex, three female groups and three male groups. Data reporting focused on the highest risk subcohort of 2840 females aged 65 or older. The DXA unit had no calibration changes during that time. Only one femoral neck-left or right-was randomly chosen for analysis. Patients with multiple qualifying exams within the time interval had one exam randomly chosen. The proof-of-principle simulation shifted the aBMD values within a range of ±10%, ±8%, ±6%, ±4%, ±3.5%, ±3%, ±2.5%, ±2%, ±1.5%, ±1%, ±0.5%, and 0 (no shift); the cross-calibration shifts were informed by published results and institutional experience. Measurement precision was modeled by randomly sampling a Gaussian distribution characterized by the worst acceptable least significant change (LSC) of 6.9%, with 100 000 samplings for each patient. T-scores were recalculated from the shifted aBMD values, followed by reassigned diagnoses from the World Health Organization's T-score-based scheme. RESULTS: The unshifted original subcohort of women aged 65 and older had 599 normal diagnoses (21.1% of the cohort), 1784 osteopenia diagnoses (62.8%), and 455 osteoporosis diagnoses (16.1%). Osteoporosis diagnosis rates were highly sensitive to aBMD shifts. At the extrema, a -10% aBMD shift led to +161% osteoporosis cases, and a +10% aBMD shift led to -64.5% osteoporosis cases. Within the more plausible ±4% aBMD error range, the osteoporosis diagnosis rate changed -10.5% per +1% aBMD shift as indicated by linear regression (R2  = 0.98). Except for the men aged 49 years and younger subcohort, the total cohort and five subcohorts had fit line slopes ranging between -9.7% and -12.1% with R2 ≥ 0.98. Cross-calibration bias had greater influence for diagnosis count rates compared to measurement precision, that is, LSC. CONCLUSIONS: These results quantify the degree of misdiagnosis that can occur in a clinically relevant cohort due to cross-calibration bias. In medical practices where patients may be scanned on more than one DXA unit, ensuring cross-calibration quality is a critical and high-value quality control task with direct impact on patient diagnosis and treatment course. The clinical impact and incidence of poor DXA quality control practices, and cross-calibration in particular, should be studied further.

Subsequent Fracture Prevention in Patients 50 Years and Older With Fragility Fractures: A Quality Improvement Initiative.

Because of osteoporosis, patients older than 50 years with fragility fractures are at risk of further fractures. We developed a quality improvement initiative based on an evidence-based Fracture Liaison Service (FLS) model of care to help prevent subsequent fractures. Previous to the implemented FLS model, less than 13% of patients with fragility fractures were assessed for osteoporosis at our institution. We created a registry tool to identify patients with fractures who were older than 50 years. Our interventions focused on identifying, contacting, and educating patients; and coordinating screening tests and an outpatient follow-up visit with an endocrinologist. Identification of patients older than 50 years with fragility fractures increased from 0% to 74.5%, with implementation of the fracture registry. Of those identified, 33.9% were screened and had a follow-up visit. The fragility fracture population older than 50 years is at risk of subsequent fractures and should be identified, contacted, educated, screened, and assessed for osteoporosis to prevent subsequent fractures.

Vitamin D deficiency, parathyroid hormone levels, and bone disease among patients with end-stage liver disease and normal serum creatinine awaiting liver transplantation.

UNLABELLED: Vitamin D deficiency is common among patients with end-stage liver disease (ESLD). The primary aim of our study was to assess the prevalence of vitamin D deficiency, secondary hyperparathyroidism, and bone disease in patients with ESLD awaiting LT. METHODS: We retrospectively studied 190 patients at our center. Serum total 25-hydroxyvitamin D (25-OH D), parathyroid hormone (PTH), calcium, and bone mineral analysis (BMA) were recorded. Standard World Health Organization (WHO) criteria were used to diagnose osteopenia/osteoporosis. Only patients with normal serum creatinine were analyzed. RESULTS: Thirty-two of 190 patients were excluded from the final analysis (missing serum total 25-OH D levels in three patients and elevated serum creatinine, 29 patients). 105 of 158 (66.4%) evaluable patients had 25-OH D levels <25 ng/mL. Patients included in the analysis (n = 158) were divided according to serum total 25-OH D levels: 0-10 ng/mL (n = 23), 11-20 ng/mL (n = 64), and >20 ng/mL (n = 71). There were no significant differences in mean serum PTH and corrected calcium levels among the three subgroups. Only three patients had elevated serum PTH. Patients with total 25-OH D ≤ 10 ng/mL had higher model for end-stage liver disease (MELD) scores vs. those with 25-OH D > 20 ng/mL (13.3 ± 3, range 8-21, vs. 11.9 ± 3.4, range 6-29, p = 0.004). Irrespective of vitamin D status, bone disease was present in 64.6% of patients. CONCLUSION: Low vitamin D levels and bone disease are common among patients with ESLD awaiting LT. Despite a high prevalence of low serum total 25-OH D, our cohort maintained normal corrected calcium levels and did not develop secondary hyperparathyroidism. We propose that free serum 25-OH D and vitamin D-binding protein may be necessary to accurately establish the diagnosis of vitamin D deficiency in the setting of ESLD. Additional studies are needed to further define mechanisms of bone disease in patients with ESLD.

Clinical and bone density outcomes of tumor-induced osteomalacia after treatment.

OBJECTIVE: To report the outcomes of tumor-induced osteomalacia after treatment, particularly related to recovery of bone mass. METHODS: We review the clinical course of a 61-year-old man extremely debilitated from multiple fractures and neuromuscular weakness due to tumor-induced osteomalacia and report the changes in biochemical markers and bone density after removal of the causative neoplasm. RESULTS: At the time of diagnosis, the patient's serum phosphorus and 1,25 dihydroxyvitamin D levels were depressed, and his fibroblast growth factor-23 level was markedly elevated. These values normalized 2 days after surgery and remained within their respective reference ranges 4 and 12 months after resection of a mesenchymal tumor. Lumbar bone density values (T-scores) were 0.445 g/cm2 (-5.9) preoperatively, 0.939 g/cm2 (-1.4) 4 months after surgery, and 1.152 g/cm2 (0.7) 12 months after surgery. Left femoral neck values at the same time points were 0.525 g/cm2 (-3.0), 1.035 g/cm2 (-0.8), and 1.184 g/cm2 (1.9). Ultra-distal radius values at the same time points were 0.128 g/cm2 (-7.0), 0.191 g/cm2 (-5.9), and 0.259 g/cm2 (-4.8). In addition, he recovered neuromuscular function and was able to leave his wheelchair. CONCLUSION: Tumor-induced osteomalacia can be an extremely debilitating disease. With successful localization, identification, and resection of the neoplasm, bone mass and physical function can recover.

Diabetes care in hospitalized noncritically ill patients: More evidence for clinical inertia and negative therapeutic momentum.

BACKGROUND: Little is known about management of hyperglycemia in inpatients. OBJECTIVE: To gain insight into caring for hospitalized patients with hyperglycemia. DESIGN: Retrospective analysis. SETTING: Teaching hospital. PATIENTS: Data on all patients discharged between January 1, 2001, and December 31, 2004 with a diagnosis of diabetes or hyperglycemia were extracted and linked to laboratory and pharmacy databases. Only the data on patients who did not require intensive care and who were hospitalized for at least 3 days were analyzed. MEASUREMENTS: Average bedside glucose during the first and last 24 hours of hospital stay and for the entire length of stay; assessment of changes in insulin regimen and dose. RESULTS: The average age of patients included in the study (n = 2916) was 69 years. Fifty-seven percent of the patients were men, 90% were white, and average length of stay was 5.7 days. More than 20% of the patients had evidence of sustained hyperglycemia. Forty-two percent of the patients who showed poor control of glycemia (glucose > 200 mg/dL) during the first 24 hours were discharged in poor control. The frequency of hypoglycemia was low (only 2.2 of 100 measurements per person) compared with hyperglycemia (25.5 of 100 measurements per person). Most patients (72%) received insulin during hospitalization, but there was high use of short-acting insulin and less than optimal intensification of therapy (clinical inertia); many patients had insulin therapy decreased despite persistent hyperglycemia (negative therapeutic momentum). CONCLUSIONS: Glycemic control in the hospital was frequently poor, and there was suboptimal use of insulin, even among patients with sustained hyperglycemia. Educational programs directed at practitioners should focus on the importance of inpatient glucose control and provide guidelines on how and when to change therapy.

Diabetes care in the hospital: is there clinical inertia?

BACKGROUND: Effective control of hospital glucose improves outcomes, but little is known about hospital management of diabetes. OBJECTIVE: Assess hospital-based diabetes care delivery. DESIGN: Retrospective chart review. SETTING: Academic teaching hospital. PATIENTS: Inpatients with a discharge diagnosis of diabetes or hyperglycemia were selected from electronic records. A random sample (5%, n = 90) was selected for chart review. MEASUREMENTS: We determined the percentage of patients with diabetes or hyperglycemia documented in admission, daily progress, and discharge notes. We determined the proportion of cases with glucose levels documented in daily progress notes and with changes in hyperglycemia therapy recorded. The frequency of hypoglycemic and hyperglycemic events was also determined. RESULTS: A diabetes diagnosis was recorded at admission in 96% of patients with preexisting disease, but daily progress notes mentioned diabetes in only 62% of cases and 60% of discharge notes; just 20% of discharges indicated a plan for diabetes follow-up. Most patients (86%) had bedside glucose measurements ordered, but progress notes tracked values for only 53%, and only 52% had a documented assessment of glucose severity. Hypoglycemic events were rare (11% of patients had at least one bedside glucose < 70 mg/dL), but hyperglycemia was common (71% of cases had at least one bedside glucose > 200 mg/dL). Despite the frequency of hyperglycemia, only 34% of patients had their therapy changed. CONCLUSIONS: Practitioners were often aware of diabetes at admission, but the problem was often overlooked during hospitalization. The low rate of documentation and therapeutic change suggests the need for interventions to improve provider awareness and enhance inpatient diabetes care.

Thymic hyperplasia presenting as anterior mediastinal mass in 2 patients with Graves disease.

Graves disease is an autoimmune thyroid condition characterized by the production of autoantibodies against the thyrotropin receptor. The autoantibodies mimic the effect of the hormone on thyroid cells, which stimulates autonomous production of thyroxine and triiodothyronine. It has been hypothesized that cross-reactivity of autoantibodies may result in Graves ophthalmopathy and dermopathy. A seldom-recognized feature of Graves disease is thymic hyperplasia. We report 2 patients with Graves disease and incidentally discovered anterior mediastinal masses presumed to be thymic hyperplasia. In both cases, these masses regressed spontaneously after treatment of hyperthyroidism.