Warming-induced monsoon precipitation phase change intensifies glacier mass loss in the southeastern Tibetan Plateau.

Glaciers are key components of the mountain water towers of Asia and are vital for downstream domestic, agricultural, and industrial uses. The glacier mass loss rate over the southeastern Tibetan Plateau is among the highest in Asia and has accelerated in recent decades. This acceleration has been attributed to increased warming, but the mechanisms behind these glaciers' high sensitivity to warming remain unclear, while the influence of changes in precipitation over the past decades is poorly quantified. Here, we reconstruct glacier mass changes and catchment runoff since 1975 at a benchmark glacier, Parlung No. 4, to shed light on the drivers of recent mass losses for the monsoonal, spring-accumulation glaciers of the Tibetan Plateau. Our modeling demonstrates how a temperature increase (mean of 0.39 ∘C ⋅dec-1 since 1990) has accelerated mass loss rates by altering both the ablation and accumulation regimes in a complex manner. The majority of the post-2000 mass loss occurred during the monsoon months, caused by simultaneous decreases in the solid precipitation ratio (from 0.70 to 0.56) and precipitation amount (-10%), leading to reduced monsoon accumulation (-26%). Higher solid precipitation in spring (+18%) during the last two decades was increasingly important in mitigating glacier mass loss by providing mass to the glacier and protecting it from melting in the early monsoon. With bare ice exposed to warmer temperatures for longer periods, icemelt and catchment discharge have unsustainably intensified since the start of the 21st century, raising concerns for long-term water supply and hazard occurrence in the region.

Declining glacier cover drives changes in aquatic macroinvertebrate biodiversity in the Cordillera Blanca, Perú.

Ongoing climate change threatens the biodiversity of glacier-fed river ecosystems worldwide through shifts in water availability and timing, temperature, chemistry, and channel stability. However, tropical glacier-fed rivers have received little attention compared to those in temperate and Arctic biomes, despite their unique biodiversity potentially responding differently due to additional stress from higher altitude locations thus lower oxygen availability, diurnal freeze-thaw cycles, and annual monsoon rainfall disturbances. However, tropical glacier-fed rivers have received little attention compared to those in temperate and Arctic biomes, despite their unique biodiversity potentially responding differently due to additional stress from higher altitude locations thus lower oxygen availability, diurnal freeze-thaw cycles, and annual monsoon rainfall disturbances. This study quantified aquatic biodiversity responses to decreasing glacier cover in the Cordillera Blanca range of the Peruvian Andes. Ten rivers were studied along a gradient of decreasing glacier cover in the Parón, Huaytapallana, and Llanganuco basins, with a specific focus on macroinvertebrates and physicochemical parameters in both the dry and wet seasons. We found higher temperatures, more stable and lower turbidity rivers as glacier cover decreased, which were related significantly to higher local diversity and lower ß-diversity. Analysis of similarity revealed significant differences in the macroinvertebrate community among rivers with high, medium, or low glacier cover, illustrating turnover from specialists to generalists as glacial influence decreased. Redundancy analysis demonstrated that there were more species found to prefer stable beds and water temperatures in medium and low glacier cover in a catchment rivers. However, certain taxa in groups such as Paraheptagyia, Orthocladiinae, Anomalocosmoecus, and Limonia may be adapted to high glacial influence habitats and at risk of glacier retreat. Although species composition was different to other biomes, the Cordillera Blanca rivers showed similar benthic macroinvertebrate biodiversity responses to glacier retreat, supporting the hypothesis that climate change will have predictable effects on aquatic biodiversity in mountain ranges worldwide.

Aspect controls the survival of ice cliffs on debris-covered glaciers.

Supraglacial ice cliffs exist on debris-covered glaciers worldwide, but despite their importance as melt hot spots, their life cycle is little understood. Early field observations had advanced a hypothesis of survival of north-facing and disappearance of south-facing cliffs, which is central for predicting the contribution of cliffs to total glacier mass losses. Their role as windows of energy transfer suggests they may explain the anomalously high mass losses of debris-covered glaciers in High Mountain Asia (HMA) despite the insulating debris, currently at the center of a debated controversy. We use a 3D model of cliff evolution coupled to very high-resolution topographic data to demonstrate that ice cliffs facing south (in the Northern Hemisphere) disappear within a few months due to enhanced solar radiation receipts and that aspect is the key control on cliffs evolution. We reproduce continuous flattening of south-facing cliffs, a result of their vertical gradient of incoming solar radiation and sky view factor. Our results establish that only north-facing cliffs are recurrent features and thus stable contributors to the melting of debris-covered glaciers. Satellite observations and mass balance modeling confirms that few south-facing cliffs of small size exist on the glaciers of Langtang, and their contribution to the glacier volume losses is very small ([Formula: see text]1%). This has major implications for the mass balance of HMA debris-covered glaciers as it provides the basis for new parameterizations of cliff evolution and distribution to constrain volume losses in a region where glaciers are highly relevant as water sources for millions of people.

Contrasting climate change impact on river flows from high-altitude catchments in the Himalayan and Andes Mountains.

Mountain ranges are the world's natural water towers and provide water resources for millions of people. However, their hydrological balance and possible future changes in river flow remain poorly understood because of high meteorological variability, physical inaccessibility, and the complex interplay between climate, cryosphere, and hydrological processes. Here, we use a state-of-the art glacio-hydrological model informed by data from high-altitude observations and the latest climate change scenarios to quantify the climate change impact on water resources of two contrasting catchments vulnerable to changes in the cryosphere. The two study catchments are located in the Central Andes of Chile and in the Nepalese Himalaya in close vicinity of densely populated areas. Although both sites reveal a strong decrease in glacier area, they show a remarkably different hydrological response to projected climate change. In the Juncal catchment in Chile, runoff is likely to sharply decrease in the future and the runoff seasonality is sensitive to projected climatic changes. In the Langtang catchment in Nepal, future water availability is on the rise for decades to come with limited shifts between seasons. Owing to the high spatiotemporal resolution of the simulations and process complexity included in the modeling, the response times and the mechanisms underlying the variations in glacier area and river flow can be well constrained. The projections indicate that climate change adaptation in Central Chile should focus on dealing with a reduction in water availability, whereas in Nepal preparedness for flood extremes should be the policy priority.

Surface Pond Energy Absorption Across Four Himalayan Glaciers Accounts for 1/8 of Total Catchment Ice Loss.

Glaciers in High Mountain Asia, many of which exhibit surface debris, contain the largest volume of ice outside of the polar regions. Many contain supraglacial pond networks that enhance melt rates locally, but no large-scale assessment of their impact on melt rates exists. Here we use surface energy balance modeling forced using locally measured meteorological data and monthly satellite-derived pond distributions to estimate the total melt enhancement for the four main glaciers within the 400-km2 Langtang catchment, Nepal, for a 6-month period in 2014. Ponds account for 0.20 ± 0.03 m/year of surface melt, representing a local melt enhancement of a factor of 14 ± 3 compared with the debris-covered area, and equivalent to 12.5 ± 2.0% of total catchment ice loss. Given the prevalence of supraglacial ponds across the region, our results suggest that effective incorporation of melt enhancement by ponds is essential for accurate predictions of future mass balance change in the region.

Health and sustainability of glaciers in High Mountain Asia.

Glaciers in High Mountain Asia generate meltwater that supports the water needs of 250 million people, but current knowledge of annual accumulation and ablation is limited to sparse field measurements biased in location and glacier size. Here, we present altitudinally-resolved specific mass balances (surface, internal, and basal combined) for 5527 glaciers in High Mountain Asia for 2000-2016, derived by correcting observed glacier thinning patterns for mass redistribution due to ice flow. We find that 41% of glaciers accumulated mass over less than 20% of their area, and only 60% ± 10% of regional annual ablation was compensated by accumulation. Even without 21st century warming, 21% ± 1% of ice volume will be lost by 2100 due to current climatic-geometric imbalance, representing a reduction in glacier ablation into rivers of 28% ± 1%. The ablation of glaciers in the Himalayas and Tien Shan was mostly unsustainable and ice volume in these regions will reduce by at least 30% by 2100. The most important and vulnerable glacier-fed river basins (Amu Darya, Indus, Syr Darya, Tarim Interior) were supplied with >50% sustainable glacier ablation but will see long-term reductions in ice mass and glacier meltwater supply regardless of the Karakoram Anomaly.

NSAID-related psychiatric adverse events: who is at risk?

NSAIDs are frequently used in clinical practice and they account for approximately 5-10% of all drug prescriptions. NSAID use has been associated with a risk of adverse events, which have a relevant impact on morbidity and mortality and account for a substantial increment of healthcare costs. Less common, but clinically relevant, adverse events associated with NSAID use are the impairment of the CNS and, particularly, the appearance of psychiatric symptoms. These symptoms include changes in cognition, mood state and even precipitation or exacerbation of pre-existing psychiatric disorders. This article aims to review the medical literature on published reports of NSAID-related psychiatric adverse events, identify risk factors for these events and describe mechanisms potentially involved in their onset. We identified 27 reports with data on 453 cases of NSAID-related psychiatric adverse events. Data suggest that individuals who may be particularly susceptible to such events include patients with a history of psychiatric illness and possibly parturients. Indometacin and selective cyclo-oxygenase (COX)-2 inhibitors were the most frequently reported culprit drugs; however, whether this reflects an increased incidence with these drugs compared with other NSAIDs or factors such as usage or reporting patterns is unknown.A possible explanation for the psychiatric effect of NSAIDs resides in the modulation of central neurotransmission by prostaglandins, the synthesis of which is inhibited by NSAIDs. COX-2 is a key enzyme in this process since its activity is localised in distal dendrites and dendritic spines, which are cellular specialisations involved in synaptic signalling. Dopamine is considered the most relevant neurotransmitter involved in this phenomenon. Psychiatric symptoms are a rare but relevant complication of NSAID use. This effect is probably a consequence of impairment in neurotransmission modulated by prostaglandins when NSAIDs are used by susceptible individuals. These drugs should be used with caution in high-risk individuals with pre-existing psychiatric illness, and caution may also be advisable in the postpartum period. To date, reports of NSAID-related psychiatric adverse events have most commonly involved indometacin and selective COX-2 inhibitors. Prescribers should consider warning patients of the possibility of an acute neuropsychiatric event when traditional NSAIDs or selective COX-2 inhibitors are prescribed.

Handgrip strength predicts persistent walking recovery after hip fracture surgery.

BACKGROUND: In older people, hip fractures often lead to disability and death. We evaluated handgrip strength, an objective measure of physical function for bedridden patients, as a predictor of walking recovery in the year after fracture surgery. METHODS: This multicenter prospective cohort study included 504 patients, aged 70 years or more, who were admitted to the hospital for hip fracture surgery and were formerly able to walk independently. A multidimensional geriatric evaluation that included a physical examination, Short Portable Mental Status Questionnaire, Geriatric Depression Scale, Charlson Index, Basic Activities of Daily Living, and grip strength was administered at the time of admission. Follow-ups were performed every 3 months for 1 year after surgery to assess functional status and survival. The walking recovery probability was evaluated using multivariable logistic regression models. RESULTS: The mean age of the participants was 85.3 ± 5.5 years, and 76.1% of the participants were women. The mean grip strength was greater in men (ß: 6.6 ± 0.62, P < .001) and was directly related to the Short Portable Mental Status Questionnaire results (P < .001), Basic Activities of Daily Living results (P < .001), serum vitamin D levels (P = .03), and time before surgery (P < .001), whereas it was inversely related to age (P < .001), Geriatric Depression Scale score (P < .001), and Charlson Index (P < .001). After adjusting for confounders, the grip strength was directly associated with the probability of both incident and persistent walking recovery (odds ratio highest tertile vs lowest tertile, 2.84, confidence interval, 1.76-4.59 and 2.79, confidence interval, 1.35-5.79, respectively). CONCLUSIONS: In older patients with hip fractures, early grip strength evaluation might provide important prognostic information regarding the patient's future functional trajectory.

Challenges in the differential diagnosis of hypercalcemia: A case of hypercalcemia with normal PTH level.

The hypercalcemias are a common and heterogeneous group of disorders, ranging from the occasional detection of a high level of serum calcium to a life-treating condition. In a patient presenting with hypercalcemia, a differential diagnosis can be established easily by measuring serum calcium and parathyroid hormone (PTH) concentrations. We describe the case of an 83-year-old man presenting with a severe symptomatic hypercalcemia with high-normal PTH level due to the coexistence of primary hyperparathyroidism and malignancy-associated hypercalcemia. The presence of two conditions producing hypercalcemia was revealed only during in-hospital stay and after the administration of an intravenous bisphosphonate, when the PTH concentration increased rapidly after bisphosphonate treatment with a decrease in serum calcium. The occurrence of two conditions producing hypercalcemia is a rare event in the literature, and should be considered in the presence of an abnormally high serum calcium level associated with normal or high-normal PTH, in order to establish a correct diagnosis and appropriate interventions.

Time to surgery and rehabilitation resources affect outcomes in orthogeriatric units.

OBJECTIVE: To compare the pathways of care and clinical results for patients admitted for hip fracture (HF) in 3 orthogeriatric co-managed care centers in order to estimate the effect of system factors on mortality and functional outcome. DESIGN: Prospective inception multicenter cohort study. SETTING: Three tertiary Hospitals. PARTICIPANTS: 806 patients consecutively admitted with HF. MEASUREMENTS: 1-Year mortality, the loss of 1 or more functional abilities in activities of daily living (ADLs), and the recovery/maintenance of independent ambulation at 6 months from the fracture. RESULTS: On the whole sample, 71.1% of patients survived 1 year from the fracture. In one hospital the risk of 1-year mortality was significantly higher even after adjusting for age, sex, comorbidity, prefracture functional status and cognitive impairment (odd ratio (OR) 1.56, 95% confidence interval (CI) 1.15-2.18, p=0.01). This was principally explained by a longer time to surgery (5.2 days ± 3.2 vs 2.7 ± 2.3 and 2.7 ± 2.2, p<0.001). The three hospitals also differed in the rate of subjects losing the ability in ADLs after 6 months from the fracture (54.2%, 61%, 43.5%, p=0.016), while no statistical differences were found in the recovery of independent ambulation. On the basis of multivariate models, a lower access to post-acute rehabilitation could account for lower outcome in functional status. CONCLUSIONS: This study suggests that system factors such as time to surgery and rehabilitation resources can affect functional recovery and 1-year mortality in orthogeriatric units and they could explain different outcomes when comparing care models.

Older people with hip fracture and IADL disability require earlier surgery.

BACKGROUND: Hip fractures represent a major challenge for physicians as well as society as a whole. Both poor functional status and delay to surgery are well known risk factors for negative outcomes. We hypothesized that the timing of the operation is more important for frail older people than older people without functional limitations before fracture. METHODS: We performed a prospective multicenter cohort study on 806 consecutive patients, 75 years of age or older, admitted with a fragility hip fracture to three hospitals in the Emilia-Romagna Region (Italy). All three hospitals had a comanaged care model, and the patients were under the shared responsibility of an orthopedic surgeon and a geriatrician. RESULTS: Functional status assessed as instrumental activities of daily living was an important predictor of survival after 1 year from fracture. After adjusting for confounders, the hazard ratios per 1 point score of increase from 0 to 8 was 1.30 (95% confidence interval 1.19-1.42, p = .000). Time to surgery increased 1-year mortality in patients with a low instrumental activities of daily living score (hazard ratios per day of surgical delay 1.14, 95% confidence interval 1.06-1.22, p < .001) and intermediate instrumental activities of daily living score (hazard ratios 1.21, 95% confidence interval 1.09-1.34, p < .001) but was an insignificant risk factor in functionally independent patients (hazard ratios 1.05 95% confidence interval 0.79-1.41, p = .706). CONCLUSIONS: Surgery delay is an independent factor for mortality in older patients after hip fracture but only for the frail older people with prefracture functional impairment. If our results are confirmed, a more intensive approach should be adopted for older people with hip fractures who have disabilities.