Global burden and strength of evidence for 88 risk factors in 204 countries and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

Background: Understanding the health consequences associated with exposure to risk factors is necessary to inform public health policy and practice. To systematically quantify the contributions of risk factor exposures to specific health outcomes, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 aims to provide comprehensive estimates of exposure levels, relative health risks, and attributable burden of disease for 88 risk factors in 204 countries and territories and 811 subnational locations, from 1990 to 2021. Methods: The GBD 2021 risk factor analysis used data from 54 561 total distinct sources to produce epidemiological estimates for 88 risk factors and their associated health outcomes for a total of 631 risk–outcome pairs. Pairs were included on the basis of data-driven determination of a risk–outcome association. Age-sex-location-year-specific estimates were generated at global, regional, and national levels. Our approach followed the comparative risk assessment framework predicated on a causal web of hierarchically organised, potentially combinative, modifiable risks. Relative risks (RRs) of a given outcome occurring as a function of risk factor exposure were estimated separately for each risk–outcome pair, and summary exposure values (SEVs), representing risk-weighted exposure prevalence, and theoretical minimum risk exposure levels (TMRELs) were estimated for each risk factor. These estimates were used to calculate the population attributable fraction (PAF; ie, the proportional change in health risk that would occur if exposure to a risk factor were reduced to the TMREL). The product of PAFs and disease burden associated with a given outcome, measured in disability-adjusted life-years (DALYs), yielded measures of attributable burden (ie, the proportion of total disease burden attributable to a particular risk factor or combination of risk factors). Adjustments for mediation were applied to account for relationships involving risk factors that act indirectly on outcomes via intermediate risks. Attributable burden estimates were stratified by Socio-demographic Index (SDI) quintile and presented as counts, age-standardised rates, and rankings. To complement estimates of RR and attributable burden, newly developed burden of proof risk function (BPRF) methods were applied to yield supplementary, conservative interpretations of risk–outcome associations based on the consistency of underlying evidence, accounting for unexplained heterogeneity between input data from different studies. Estimates reported represent the mean value across 500 draws from the estimate's distribution, with 95% uncertainty intervals (UIs) calculated as the 2·5th and 97·5th percentile values across the draws. Findings: Among the specific risk factors analysed for this study, particulate matter air pollution was the leading contributor to the global disease burden in 2021, contributing 8·0% (95% UI 6·7–9·4) of total DALYs, followed by high systolic blood pressure (SBP; 7·8% [6·4–9·2]), smoking (5·7% [4·7–6·8]), low birthweight and short gestation (5·6% [4·8–6·3]), and high fasting plasma glucose (FPG; 5·4% [4·8–6·0]). For younger demographics (ie, those aged 0–4 years and 5–14 years), risks such as low birthweight and short gestation and unsafe water, sanitation, and handwashing (WaSH) were among the leading risk factors, while for older age groups, metabolic risks such as high SBP, high body-mass index (BMI), high FPG, and high LDL cholesterol had a greater impact. From 2000 to 2021, there was an observable shift in global health challenges, marked by a decline in the number of all-age DALYs broadly attributable to behavioural risks (decrease of 20·7% [13·9–27·7]) and environmental and occupational risks (decrease of 22·0% [15·5–28·8]), coupled with a 49·4% (42·3–56·9) increase in DALYs attributable to metabolic risks, all reflecting ageing populations and changing lifestyles on a global scale. Age-standardised global DALY rates attributable to high BMI and high FPG rose considerably (15·7% [9·9–21·7] for high BMI and 7·9% [3·3–12·9] for high FPG) over this period, with exposure to these risks increasing annually at rates of 1·8% (1·6–1·9) for high BMI and 1·3% (1·1–1·5) for high FPG. By contrast, the global risk-attributable burden and exposure to many other risk factors declined, notably for risks such as child growth failure and unsafe water source, with age-standardised attributable DALYs decreasing by 71·5% (64·4–78·8) for child growth failure and 66·3% (60·2–72·0) for unsafe water source. We separated risk factors into three groups according to trajectory over time: those with a decreasing attributable burden, due largely to declining risk exposure (eg, diet high in trans-fat and household air pollution) but also to proportionally smaller child and youth populations (eg, child and maternal malnutrition); those for which the burden increased moderately in spite of declining risk exposure, due largely to population ageing (eg, smoking); and those for which the burden increased considerably due to both increasing risk exposure and population ageing (eg, ambient particulate matter air pollution, high BMI, high FPG, and high SBP). Interpretation: Substantial progress has been made in reducing the global disease burden attributable to a range of risk factors, particularly those related to maternal and child health, WaSH, and household air pollution. Maintaining efforts to minimise the impact of these risk factors, especially in low SDI locations, is necessary to sustain progress. Successes in moderating the smoking-related burden by reducing risk exposure highlight the need to advance policies that reduce exposure to other leading risk factors such as ambient particulate matter air pollution and high SBP. Troubling increases in high FPG, high BMI, and other risk factors related to obesity and metabolic syndrome indicate an urgent need to identify and implement interventions

Abnormal intraparotid termination of facial vein and its clinical importance.

Facial vein is the main vein of the face. Though its origin is constant, it frequently shows variations in its termination. We report a rare type of variation of facial vein. The right facial vein coursed transversely across the masseter, superficial to the parotid duct and entered into the substance of the parotid gland, at its anterior border. Deep dissection of the gland revealed the abnormal termination of facial vein into the superficial temporal vein. The transverse facial vein drained into the facial vein. The superficial temporal vein after receiving the facial vein continued as retromandibular vein. Knowledge of this anomalous course and termination of facial vein may be important for the surgeons doing parotid, maxillofacial and plastic surgeries

Unusual Termination of Facial Artery Associated with the Presence of Premasseteric Branch- A Case Report.

Face being highly vascular region essentially receives extensive blood supply from the facial artery. Facial artery frequently shows variation in its pattern of origin, course and termination. An unusual premasseteric branch is the one among its variant branches on the face. We report herewith the untimely termination of facial artery as alar artery at the nose instead of medial angle of the eye associated with an abnormally large posterior branch known as premasseteric branch. Presence of premasseteric artery may be considered as beneficial in ‘raising flap’ approaches. However, ascertaining its existence makes obligatory for the surgeons during surgical procedures of the face

Unique Case of Entwined Left Testicular and Left Renal Artery Forming an Arterial Arch Over the Left Renal Vein

Testicular arteries are the main arteries supplying the testis. An anatomical variation in the course of the left testicular artery and left renal artery is presented in this case report, highlighting its clinical implications. The left testicular artery had a high origin from the anterior aspect of the abdominal aorta and took a recurrent course. On reaching the upper border of the left renal vein, it looped over it and descended in front of it. The left renal artery had normal origin and normal course of its proximal half. Thereafter, it arched over the superior border of renal vein and appeared on its anterior surface to reach the renal hilum, causing a mild tortuous course of the artery. This arching of testicular artery and renal artery over the left renal vein might compress the renal vein resulting in renal vein hypertension. This unusual course might also compress the testicular artery causing testicular and pelvic varicocele. Hence, an abnormal course of testicular artery often warrants clinical attention because of its importance in maintaining thermoregulation and proper spermatogenesis of the testis

Incidental Case of Metastatic Squamous Cell Carcinoma in the Posterior Thoracic Wall: A Cadaveric Finding

Occurrence of secondary tumors from visceral carcinomas on the thoracic cage represent a relatively rare form of metastasis. We present in this report an extremely rare case of an incidental finding of tumor mass (squamous cell carcinoma) in the thoracic wall of an adult male cadaver. During routine dissection of thoracic cavity, we noticed this unique tumor in the posterior thoracic wall. Its gross measurements were noted and a small piece of the tumor mass was processed for histopathological examination, to confirm its nature. The H&E stained section showed presence of infiltrating tumor composed of islands of squamous cells with pleomorphic nuclei, course chromatin, scattered dyskeratotic cells and foci of keratin pearl formation, which confirmed the tumor to be secondary metastatic squamous cell carcinoma. Such metastatic tumors with very rare occurrence are an interesting diagnostic and therapeutic challenge for thoracic surgeons

A unique case of bifid left testicular artery having its anomalous high origin from renal artery

The testicular arteries are known to originate from the ventrolateral aspect of the abdominal aorta and descend obliquely to the pelvic cavity and supply the testis. An anatomical description of an uncommon variation of the left testicular artery is presented in this case report, highlighting its clinical implications. During routine dissection of a male cadaver, we found that the left testicular artery was bifid and it was arising from the left renal artery. After its origin, it then coursed behind the left renal vein, passed between the left testicular vein and left ureter and at the lower pole of the left kidney, this bifid testicular artery joined to form a single testicular artery which thereafter presented a normal course. Anatomy of the testicular artery has been studied in detail because of its importance in testicular physiology, as well as its significance in testicular and renal surgery. This vascular variation shows a major significance in renal surgery, partial or total nephrectomy, and renal transplant. In addition, this anatomical variation enhances the importance of arteriography or the Doppler ultrasound examination of the renal hilum before surgeries

A peculiar accessory renal artery giving origin to the left testicular artery

The occurrence of the accessory left renal artery (ALR) and its giving origin to the left testicular artery (LTA) is not a common variation. We report a rare type of course and branching of an ALR which was observed in an approximately 65-year-old male cadaver of the Indian origin. The left kidney (LK) was supplied by two renal arteries (RA). The main RA arose from the abdominal aorta (AA) and then reached the LK by passing above the renal vein. It gave three segmental branches before entering into the hilum. The ALR was smaller in size than the main RA and it arose from the AA below the level of the main RA. It hooked around the left renal vein (LRV) and entered into the hilum without branching, passing posterior the renal vein. ARA presented a peculiar S shape in its course. Further, the ALR gave origin to LTA at its middle segment. The LRV was normal in formation, course and drainage. Knowledge of the unusual perihilar vascular variations of the kidney is of significance during the radiologic and angiographic and surgical procedures

Scholars Journal of Medical Case Reports ISSN 2347-9507 (Print) Incomplete duplicated (bifid) left ureter -A case report

Abstract: The ureter is subjected to natural variation such as duplication. The partial duplication forming bifidity is one of its rare congenital anomalies. We report here a case of unilateral left bifid ureter encountered during cadaveric dissection. The bifidity in the present case was at its greater extent and in the form of Y shaped with superior and inferior segments. Proximally, both the segments arose from the renal hilum. At pelvic brim, superior segment crossed the inferior segment superficially from medial to lateral. Both the segments united in the lesser pelvis at the level of bifurcation of internal iliac artery, about 1.5 inches above its opening into urinary bladder. Bifid ureter may be associated with the renal stones and other pathological conditions like gonadal dysgenesis. Knowledge of bifid ureter with the extent of bifidity is important during diagnostic approaches of associated disorders. Since the ureter is closely related to neighbouring vessels and organs, its detailed anatomy is essential in surgical and radiological interventional approaches

An eccentric anatomical variation of palmar vascular pattern: Report of surgical challenging vascular variation

The knowledge of variations in the vascular architecture of hand is of great importance to surgeons, orthopedicians, and plastic surgeons in microsurgical procedures following crush injuries of the hand and amputations. The efficiency of collateral circulation in hand is essential in few peripheral vascular diseases like Raynaud′s disease and harvesting of the radial artery for the coronary bypass graft. During routine dissection of the right upper limb of a 55-year-old male cadaver, we observed that the superficial palmar arch (SPA) is formed by the ulnar artery and completed by the first dorsal metacarpal artery. After completing the arch, dorsal metacarpal artery continued as princeps pollicis artery for the thumb. The common palmar digital artery supplying the contiguous side of index and middle fingers passed through the neural loop formed by the proper digital nerve supplying the radial side of the middle finger and joined with the unusually large first palmar metacarpal artery before dividing into proper digital arteries. The first palmar metacarpal artery also gave origin to radialis indicis artery which in turn ran deep to tendons of the index finger to reach index finger. The common palmar digital artery supplying the contiguous side of middle and ring fingers also passed through the neural loop formed by the proper digital nerve supplying the ulnar side of the middle finger. The deep palmar branch of ulnar artery gave proper digital artery to little finger