U

Usman Ahmad

Shaukat Khanum Memorial Cancer Hospital and Research Center

ORCID: 0000-0001-9159-6791

Publishes on Pancreatic and Hepatic Oncology Research, Lymphoma Diagnosis and Treatment, Acute Lymphoblastic Leukemia research. 56 papers and 438 citations.

56Publications
438Total Citations

Is this you? Claim your profile.

Add your photo, update your bio, and get notified when your ranking changes.

Top publicationsby citations

The Pakistan Risk of Myocardial Infarction Study: a resource for the study of genetic, lifestyle and other determinants of myocardial infarction in South Asia
Danish Saleheen, Moazzam Zaidi, Asif Rasheed et al.|European Journal of Epidemiology|2009
Cited by 112Open Access

The burden of coronary heart disease (CHD) is increasing at a greater rate in South Asia than in any other region globally, but there is little direct evidence about its determinants. The Pakistan Risk of Myocardial Infarction Study (PROMIS) is an epidemiological resource to enable reliable study of genetic, lifestyle and other determinants of CHD in South Asia. By March 2009, PROMIS had recruited over 5,000 cases of first-ever confirmed acute myocardial infarction (MI) and over 5,000 matched controls aged 30-80 years. For each participant, information has been recorded on demographic factors, lifestyle, medical and family history, anthropometry, and a 12-lead electrocardiogram. A range of biological samples has been collected and stored, including DNA, plasma, serum and whole blood. During its next stage, the study aims to expand recruitment to achieve a total of about 20,000 cases and about 20,000 controls, and, in subsets of participants, to enrich the resource by collection of monocytes, establishment of lymphoblastoid cell lines, and by resurveying participants. Measurements in progress include profiling of candidate biochemical factors, assay of 45,000 variants in 2,100 candidate genes, and a genomewide association scan of over 650,000 genetic markers. We have established a large epidemiological resource for CHD in South Asia. In parallel with its further expansion and enrichment, the PROMIS resource will be systematically harvested to help identify and evaluate genetic and other determinants of MI in South Asia. Findings from this study should advance scientific understanding and inform regionally appropriate disease prevention and control strategies.

Association of the 9p21.3 Locus With Risk of First-Ever Myocardial Infarction in Pakistanis
Danish Saleheen, M Alexander, Asif Rasheed et al.|Arteriosclerosis Thrombosis and Vascular Biology|2010
Cited by 54

OBJECTIVE: To examine variants at the 9p21 locus in a case-control study of acute myocardial infarction (MI) in Pakistanis and to perform an updated meta-analysis of published studies in people of European ancestry. METHODS AND RESULTS: A total of 1851 patients with first-ever confirmed MI and 1903 controls were genotyped for 89 tagging single-nucleotide polymorphisms at locus 9p21, including the lead variant (rs1333049) identified by the Wellcome Trust Case Control Consortium. Minor allele frequencies and extent of linkage disequilibrium observed in Pakistanis were broadly similar to those seen in Europeans. In the Pakistani study, 6 variants were associated with MI (P<10(-2)) in the initial sample set, and in an additional 741 cases and 674 controls in whom further genotyping was performed for these variants. For Pakistanis, the odds ratio for MI was 1.13 (95% CI, 1.05 to 1.22; P=2 x 10(-3)) for each copy of the C allele at rs1333049. In comparison, a meta-analysis of studies in Europeans yielded an odds ratio of 1.31 (95% CI, 1.26 to 1.37) for the same variant (P=1 x 10(-3) for heterogeneity). Meta-analyses of 23 variants, in up to 38,250 cases and 84,820 controls generally yielded higher values in Europeans than in Pakistanis. CONCLUSIONS: To our knowledge, this study provides the first demonstration that variants at the 9p21 locus are significantly associated with MI risk in Pakistanis. However, association signals at this locus were weaker in Pakistanis than those in European studies.

COVID 19 and BAME health care staff: Wrong place at the wrong time
Faisal Bashir Chaudhry, Samavia Raza, Khurram Zeeshan Raja et al.|Journal of Global Health|2020
Cited by 34Open Access

O f the 1.2 million staff employed by NHS, 20.7% belong to Black, Asian and minority ethnic (BAME) background. However, analysis of deaths of NHS Staff during the pandemic shows that 64% of those who died belonged to BAME background. A recent survey about this disproportionately high mortality has suggested discriminatory deployment of staff from non-white ethnic background in areas with potentially high virus exposure as a reason. We have looked at factors to explain this heavy presence of medical staff from BAME background at the front door. Moreover, we have studied mortality data related to COVID-19 and analysed it against population demographics of corresponding areas of west midlands, to highlight any trends. This has revealed a higher mortality form COVID 19 in cohorts with higher percentage of BAME population.

Genetic Determinants of Major Blood Lipids in Pakistanis Compared With Europeans
Danish Saleheen, Nicole Soranzo, Asif Rasheed et al.|Circulation Cardiovascular Genetics|2010
Cited by 27Open Access

BACKGROUND: Evidence is sparse about the genetic determinants of major lipids in Pakistanis. METHODS AND RESULTS: Variants (n=45 000) across 2000 genes were assessed in 3200 Pakistanis and compared with 2450 Germans using the same gene array and similar lipid assays. We also did a meta-analysis of selected lipid-related variants in Europeans. Pakistani genetic architecture was distinct from that of several ethnic groups represented in international reference samples. Forty-one variants at 14 loci were significantly associated with levels of HDL-C, triglyceride, or LDL-C. The most significant lipid-related variants identified among Pakistanis corresponded to genes previously shown to be relevant to Europeans, such as CETP associated with HDL-C levels (rs711752; P<10(-13)), APOA5/ZNF259 (rs651821; P<10(-13)) and GCKR (rs1260326; P<10(-13)) with triglyceride levels; and CELSR2 variants with LDL-C levels (rs646776; P<10(-9)). For Pakistanis, these 41 variants explained 6.2%, 7.1%, and 0.9% of the variation in HDL-C, triglyceride, and LDL-C, respectively. Compared with Europeans, the allele frequency of rs662799 in APOA5 among Pakistanis was higher and its impact on triglyceride concentration was greater (P-value for difference <10(-4)). CONCLUSIONS: Several lipid-related genetic variants are common to Pakistanis and Europeans, though they explain only a modest proportion of population variation in lipid concentration. Allelic frequencies and effect sizes of lipid-related variants can differ between Pakistanis and Europeans.

Efficiency Analysis of Micro-finance Institutions in Pakistan
Usman Ahmad|Munich Personal RePEc Archive (Ludwig Maximilian University of Munich)|2011
Cited by 27Open Access

Microfinance collectively refers to the supply of loans, savings accounts, and other basic financial services like insurance, to the poor. About one billion people globally live in households with per capita incomes of one dollar per day (Morduch J. 1999). Microfinance Institutions (MFIs) are special financial institutions. They have both a social nature and a for-profit nature. Their performance has been traditionally measured by means of financial ratios. The objective of the study has been to estimate the efficiency of microfinance institutions in Pakistan. Non parametric Data Envelopment analysis has been used to analyze the efficiency of these institutions by using data for the year 2003 and 2007 respectively. Both input oriented and output oriented methods have been considered under the assumption of constant return to scale technologies and microfinance should provide services on sustainable basis. A microfinance institution is said to be financially sustainable if it without the use of subsidies, grants, or other concessional resources, it can profitably provide finance to micro enterprises on an acceptable scale.