草島 邦夫

PURPOSE: To develop and validate a prediction model for sleep apnea syndrome (SAS) treated with continuous positive airway pressure (CPAP) in the general population. METHODS: Using claims and health checkup data held by JMDC Inc. linked to personal health records (Pep Up), we developed and internally validated a prediction model for SAS treated with CPAP, defined as a SAS diagnosis and reimbursement records of CPAP. Every 3 months from January 1, 2022 to July 1, 2024 (11 timepoints), we identified eligible individuals with available data both 1 year before and after that timepoint to define the presence/absence of SAS treated with CPAP, along with 279 predictor variables. We developed a LightGBM model for the training and tuning datasets and evaluated its performance on the validation dataset. RESULTS: Overall, 18,692,873 observations (mean age: 44.8 ± 11.3 years; female, 37.5%) were obtained from 1,858,566 individuals; of these observations, 300,868 observations (1.6%) were found to have SAS treated with CPAP. The area under the receiver operating characteristic curve was 0.898 (95% confidence interval 0.895-0.901). The positive predictive values among observations in the top 1% and 10% of predicted risk were 28.3% and 10.3%, respectively. According to the SHapley Additive exPlanations plots, male sex was the most important predictor, followed by age, body mass index, and waist circumference. Moreover, personal health records significantly improved the predictive performance. CONCLUSION: We developed a prediction model to identify individuals at high risk of SAS treated with CPAP and encourage them to undergo polysomnography or related tests.

A 76-year-old woman with cervical cancer was treated with nedaplatin, a platinum-based drug. After the initiation of the treatment, she became aware of numbness, dizziness, and loss of appetite. Exploration of the causes revealed no clues, but blood tests revealed hypocalcemia and hypomagnesemia. She was treated with intravenous calcium and magnesium, which resolved calcium, magnesium levels, and her symptoms. She was diagnosed with hypomagnesemia because of nedaplatin. Regular follow-up is necessary for patients during or after nedaplatin. Awareness of electrolyte disturbances may elucidate the accurate diagnosis even in patients with obscure symptoms, particular in undergoing or following anticancer therapies.

医学部低学年に在籍する筆頭著者が，医療機関で多職種業務を実践し，成員となっていく過程を「正統的周辺参加理論」に基づき考察した．学習者と実践共同体の間に互恵的関係が構築される過程で，学習者の学びが促進され，実践共同体の成員として認められた．さらに，実践共同体にも建設的な変化が観察された．本活動は医学生にとって有意義な学習機会であり，転用性の高い活動となりうる．

BACKGROUND: Symptomatic anterior mediastinal mass in pregnancy is rare, and cesarean section for such patients poses a risk of cardiopulmonary collapse. CASE PRESENTATION: A 30-year-old woman at 40 weeks' gestation complained of breathlessness and cough, and she was not able to lie supine because of respiratory distress. Computed tomography scan revealed a large anterior-superior mediastinal mass severely compressing the trachea, bilateral main bronchus, and superior vena cava. Because clinical symptoms and computed tomographic findings suggested imminent respiratory catastrophe, urgent cesarean section was planned. The patient was able to lie in the semi-recumbent position with minimal symptoms; therefore, we considered it safe to perform cesarean section with combined spinal epidural anesthesia. In the event of cardiopulmonary collapse, emergent intubation and extracorporeal membrane oxygenation were also planned. The operation was performed successfully with combined spinal epidural anesthesia. The infant was healthy, and the postoperative hospital course was uneventful. CONCLUSIONS: Combined spinal epidural anesthesia is preferable in the anesthetic management of cesarean section with symptomatic anterior mediastinal mass. A well-designed preoperative strategy can lead to favorable outcomes even in this complicated situation.

OBJECTIVES: Concomitant tricuspid valve surgery with mitral valve surgery is recommended for patients with severe functional tricuspid regurgitation (TR). However, the treatment for 2+ TR (mild TR) remains controversial. Here, we evaluated the long-term results of untreated 2+ TR in patients undergoing mitral valve surgery. METHODS: We retrospectively reviewed the records of 96 patients with untreated 2+ TR among 885 patients who underwent mitral valve surgery from 2003 to 2010. Exclusion criteria were tricuspid valve surgery (TVS), emergency surgery, primary TR and pacemaker lead through the tricuspid valve. We assessed survival and freedom from heart failure. The freedom from 3+ (moderate) or 4+ (severe) TR was investigated by echocardiographic data at pre- and postoperative week 1, then at 1, 3, 5, 7 and 10 postoperative years, which were compared with those in patients who had 2+ TR preoperatively and underwent concomitant TVS in the same period (n = 47). RESULTS: The mean follow-up was 7.1 ± 2.7 years. There was no 30-day mortality. The survival rate was 97.5% at 5 years and 87.5% at 10 years. The independent risk factors for mortality were age (OR 1.2, P = 0.03) and left ventricular ejection fraction (OR 0.9, P = 0.03). Untreated 2+ TR improved transiently within the first postoperative year (P < 0.001), but progressed again in the mid- to long term. Freedom from ≥3+ TR was 64.2% at 5 years and 46.7% at 10 years, which was significantly lower than that from ≥3+ TR in patients who underwent concomitant TVS (P = 0.006). The independent risk factors for TR progression (≥3 + TR) were age (OR 1.1, P = 0.005), atrial fibrillation (OR 2.2, P = 0.04) and tricuspid annular diameter (TAD) index (mm/m(2); OR 1.1, P = 0.02). Receiver operating characteristic curves showed that the optimal TAD index cut-off value was 21.0 for long-term survival [area under the curve (AUC) = 0.72] and 21.2 for TR progression (AUC = 0.64). CONCLUSIONS: Although untreated, 2+ TR significantly improved after mitral valve surgery, it then progressed again in the mid- to long term. Therefore, concomitant TVS should be considered in patients with 2+ TR who have dilated tricuspid annulus or atrial fibrillation, if feasible.