Prevalence Of Retinitis Pigmentosa Research Articles

Prevalence of Retinitis Pigmentosa in a Tertiary Eye Hospital of Nepal.

Retinitis Pigmentosa (RP) is a group of diffuse retinal degenerative diseases predominantly affecting the rod and cone photoreceptors. The prevalence of retinitis pigmentosa seen in literature is approximately 1:4000. Retinitis Pigmentosa is one of the the most common causes of blindness in the age group of 20 to 40 years. The objective of this study was to determine the profile of retinitis pigmentosa in Terai and Nepal-India border region considering patients seeking care at a Tertiary level Eye Hospital in the terai region (southern part) of Nepal. A hospital-based, retrospective study was carried out at R. M. Kedia Eye Hospital. A total of 385 (83 males and 107 females from Nepal and 109 males and 86 females from India) diagnosed patients of Retinitis Pigmentosa were included in the study. Data was collected over a period of eleven years from 2008-2018. Out of 385 diagnosed Retinitis Pigmentosa patients, 192 (49.87%) were male and 193 (50.13%) were female with slightly female predominance. The prevalence of RP seen in our study was 0.03%. About 51% of the patients visited here were from India and nearby border areas/ villages which cover most of the rural areas of India. In this study it was found that 49.34% of the RP cases were from Nepal, of which 43.63% of cases were from Hindu community and 5.71% from Muslim community and about 50.66% cases of RP were from India, of which 37.67% from Hindu and 12.98% from Muslim community. The peak age of presentation of RP was at 30-39 years (29.09%), followed by 20-29 years (26.75%). The common marriage pattern of consanguinity was found in Muslim community in between the first cousins. In this study the hospital record did not show any evaluation for the syndromic disease in the hospital record, though RP is usually non syndromic and there are literatures where many syndromic forms have been identified. The prevalence of RP seen in the study was 0.03% (A total of 1101299 sample population of which 385 patients had RP). Since RP is an inherited disease and is one of the non-treatable causes of blindness which runs in the families, a role of counseling to reduce consanguineous marriages should be brought forward to reduce the disease process.

Prevalence, Age at Diagnosis, Mortality, and Cause of Death in Retinitis Pigmentosa in Korea—A Nationwide Population-based Study

To determine the prevalence and mortality of retinitis pigmentosa (RP) patients in Korea. Population-based retrospective cohort study. We used data covering the 2011-2014 period from the Rare Intractable Disease (RID) registry and Health Insurance Review and Assessment (HIRA) service, which include information on all patients diagnosed with RP based on predefined diagnostic criteria. Using the HIRA-RID database, we evaluated the prevalence and age at diagnosis of RP patients across the entire Korean population. We further linked the data from Statistics Korea to the HIRA-RID database to confirm mortality and causes of death. The prevalence in the total population across all ages was 11.09 per 105 people, and the prevalence in those over the age of 40 was 16.16 per 105 people. The age at diagnosis ranged from 0 to 95 and, on average, was 44.8. The standardized mortality ratio (SMR) was 1.56 for all ages, peaking at 2.61 in men aged 40-59, which was attributed to 6.6-fold higher suicide rates than the same age group in the general male population. This is the first nationwide epidemiologic study of RP patients covering the entire population of all ages. The results suggest that the prevalence of RP in Korea is about 1 in 9000 for all ages and 1 in 6000 for those over 40 years of age. The higher mortality of RP patients than that of the general population is attributable to a high suicide rate in male RP patients of working ages, which necessitates a careful attention to their mental health.

Next-generation sequencing-based molecular diagnosis of 35 Hispanic retinitis pigmentosa probands.

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal diseases. The prevalence of RP and the mutation spectrum vary across populations. Hispanic people account for approximately 17% of the United States population, and the genetic etiologies of RP of this ethnic group still remain not well defined. Utilizing next-generation sequencing (NGS), we screened mutations in known retinal disease-causing genes in an RP cohort of 35 unrelated Hispanic probands from the Miami area. We achieved a solving rate of 66% and identified 15 novel putative pathogenic mutations, including a frequent founder mutation disrupting PRPF31 splicing. Our data show that the mutation spectrum of Hispanic RP receives a significant impact from disease-causing alleles of Spanish origin and may also contain population-specific alleles.

Optical Coherence Tomographic Analysis of Retina in Retinitis Pigmentosa Patients

Retinitis pigmentosa (RP) is a progressive inherited retinal disease characterized by nyctalopia, visual field constriction, and reduced full-field electroretinograms. The progressive loss of photoreceptors leads to vision loss at the end stage of RP. The prevalence of RP is approximately 1/4,000. Since it is one of the major causes of visual impairment worldwide, morphological and functional assessments are useful for estimating the retinal structure and function in RP. Optical coherence tomography (OCT) is a well-established method of examining retinal structure in situ, and the obtained images by OCT help to analyze morphological abnormalities. Changes revealed by OCT have provided insights into the pathology of RP as well as for predicting the prognosis of RP. In this review, we present the typical morphological changes in RP and their relationships with visual function in eyes with RP.

Next-Generation Sequencing–Based Molecular Diagnosis of a Chinese Patient Cohort With Autosomal Recessive Retinitis Pigmentosa

Retinitis pigmentosa (RP) is a highly heterogeneous genetic disease; therefore, an accurate molecular diagnosis is essential for appropriate disease treatment and family planning. The prevalence of RP in China had been reported at 1 in 3800, resulting in an estimated total of 340,000 Chinese RP patients. However, genetic studies of Chinese RP patients have been very limited. To date, no comprehensive molecular diagnosis has been done for Chinese RP patients. With the emergence of next-generation sequencing (NGS), comprehensive molecular diagnosis of RP is now within reach. The purpose of this study was to perform the first NGS-based comprehensive molecular diagnosis for Chinese RP patients. Thirty-one well-characterized autosomal recessive RP (arRP) families were recruited. For each family, the DNA sample from one affected member was sequenced using our custom capture panel, which includes 163 retinal disease genes. Variants were called, filtered, and annotated by our in-house automatic pipeline. Twelve arRP families were successfully molecular diagnosed, achieving a diagnostic rate of approximately 40%. Interestingly, approximately 63% of the pathogenic mutations we identified are novel, which is higher than that observed in a similar study on European descent (45%). Moreover, the clinical diagnoses of two families were refined based on the pathogenic mutations identified in the patients. We conclude that comprehensive molecular diagnosis can be vital for an accurate clinical diagnosis of RP. Applying this tool on patients from different ethnic groups is essential for enhancing our knowledge of the global spectrum of RP disease-causing mutations.

Prevalence of retinitis pigmentosa in India: the Central India Eye and Medical Study

Prevalence of retinitis pigmentosa in India: the Central India Eye and Medical Study

Prevalence of Retinitis Pigmentosa in South Indian Population Aged Above 40 Years

Purpose: The study was undertaken to evaluate the prevalence of retinitis pigmentosa (RP) in rural and urban South India. Methods: Seven thousand seven hundred and seventy four subjects aged 40 years or more from rural and urban Tamil Nadu, underwent comprehensive ophthalmic examination out of 9576 enumerated (81.17%). After a thorough ophthalmic examination, fundus photographs were taken for documentation. Statistical analysis was done using SPSS for Windows (ver 14). Results: 7461 (95.9%) subjects had fundus details seen in both eyes. Thirteen subjects (0.17%; 4 males, 9 females) were diagnosed as retinitis pigmentosa. Retinitis pigmentosa in the urban population was seen in approximately 1 in 930 persons, while 1 in 372 of rural subjects had the disorder. This figure is greater than other reports from the western populations and that of the conservative estimate of 1 in 4000. The age and gender adjusted prevalence rate of retinitis pigmentosa to national census 2001 was 0.155%. Eight subjects (61.53%) had visual acuity less than 3/60. Conclusion: Prevalence of RP in South India appears to be alarmingly higher in comparison to those seen in other parts of the world.

Multicenter genetic study of retinitis pigmentosa in Japan: II. Prevalence of autosomal recessive retinitis pigmentosa

Retinitis pigmentosa (RP) is a group of genetically heterogeneous diseases with autosomal recessive (AR), autosomal dominant, and X-linked modes of inheritance. Autosomal recessive retinitis pigmentosa (ARRP) is the most common form in Japan. A genetic analysis was done to determine the prevalence of ARRP indirectly, to provide an estimation of changing trends in the overall prevalence of RP. Data on the frequency of consanguinity and marriage year of normal parents of 59 ARRP patients were obtained from a nationwide multicenter survey of typical retinitis pigmentosa conducted in 1990. The gene frequency of ARRP was 0.01145 (Dahlberg's formula). In 1990, the number of young symptomatic ARRP patients decreased, while the number of patients aged 40 years and older increased. The total number of symptomatic ARRP patients in 1990 was nearly 21% higher than in 1970. Despite a dramatic decline in consanguinity in recent decades in Japan, the number of ARRP patients has increased. This increase is attributed to greater longevity and overall population growth. Our results suggest that the total number of RP patients has not decreased, and may even have increased.

Prevalence of retinitis pigmentosa and allied disorders in Denmark. III. Hereditary pattern.

A national epidemiological study revealed 1301 prevalent cases of retinitis pigmentosa (RP) in the Danish population on January 1, 1988. The corresponding number of 974 families were analyzed with respect to Mendelian inheritance groups. Thirty families, comprising 6.9% of the prevalent RP-cases, were categorized with an autosomal dominant inheritance pattern. In 187 families, 22.6% of RP-cases, autosomal recessive heredity was encountered. X-linked heredity was found in 45 families, 10.8% of the RP-cases. Simplex RP-cases comprised 562 persons (43.2% of RP-cases). About a fourth of the non-systemic X-linked cases were females. Half of these had an age at onset after 30 years, but a third had their first RP-symptoms before age 18 years. A representative fraction of parents to non-systemic autosomal dominant, autosomal recessive, X-linked, and simplex cases were evaluated concerning their age at the time they had their first affected child. Mothers of the male simplex cases were of statistically significant higher age than mothers of the other inheritance groups. This may imply a high rate of new mutations among simplex cases, especially on the X-chromosome.

Prevalence of retinitis pigmentosa and allied disorders in Denmark. II. Systemic involvement and age at onset.

A population survey of retinitis pigmentosa and allied disorders in the Danish population disclosed 1301 cases prevalent in Denmark per January 1, 1988. Crude prevalence rates and World Standardized prevalences of systemic and non-systemic RP are presented. Sixty-four per cent of all RP-cases were non-systemic. A preponderance of males was encountered in both systemic and non-systemic RP. Usher disease was diagnosed in 12%, Bardet-Biedl syndrome constituted 5%, and the frequency of Spielmeyer-Vogt disease was 1% of all prevalent RP-cases. Other defined syndromes occurred in 1% of the cases. The Danish figures with respect to Usher disease are compared with standardized prevalence rates from Sweden and Finland. Nineteen per cent of patients affected by non-systemic RP had an onset later than 30 years of age. In patients affected by systemic RP the eye disease tended to an earlier debut with only a few per cent beginning after the age of 30 years.

Prevalence of retinitis pigmentosa and allied disorders in Denmark. I Main results.

In a nation-wide study we utilized all available sources to characterize the prevalence rates of retinitis pigmentosa. 1301 persons, 715 males and 586 females, were identified, with a diagnosis of retinitis pigmentosa or some other tapetoretinal dystrophy, and living in Denmark per January 1, 1988. The corresponding completeness corrected prevalence rate of retinitis pigmentosa was 1:3026. All cases were classified as 'certain', 'probable', or 'possible'. The age specific prevalence rates increased until 40-50 years, reaching a level of 35-40 male cases per 100,000 and 25-30 female cases per 100,000. Age specific prevalence rates were standardized to the WHO World Standard Population and compared to rates reported from Britain and The United States. World standardized prevalence rate for males was 25.29 per 100,000 and for females 19.31 per 100,000. The preponderance of males was highly statistically significant, (P less than 0.01).

Estimation of prognosis and prevalence of retinitis pigmentosa and Usher syndrome in Norway.

Retinitis pigmentosa was diagnosed in 101 persons from 53 families. The prognosis for visual function was most favourable for the autosomal dominant group (38 patients from 8 families). The autosomal recessive group (40 patients from 25 families) and the 19 solitary cases were very heterogeneous, with prognosis ranging from favourable to very bad. There was a higher intrafamiliar correlation in the autosomal recessive than in the autosomal dominant group. In 28 patients from 18 families with Usher syndrome, almost all had good visual function until 30 years of age, and few had useful visual function after the age of 50. The age when the patients were registered varied between the different genetic types of retinitis pigmentosa, reflecting differences in prognosis. Therefore, ascertainment probability and prevalence were calculated for each genetic group separately. The prevalence of retinitis pigmentosa in Norway, all genetic groups included, was calculated to be 1/4440, the autosomal dominant type of the disease being the most frequent. The prevalence of Usher syndrome was calculated to be 3.6/100,000. Both retinitis pigmentosa and Usher syndrome were more prevalent in Laps.

Prevalence of Retinitis Pigmentosa in Maine

Between 1976 and 1980, medical and social service sources were used to ascertain cases of retinitis pigmentosa in Maine (1980 population, I, 124,660). As of July 1, 1980, 241 clinically prevalent cases of retinitis pigmentosa were ascertained. Extensive pedigrees were collected for 185 of the subjects and medical records were obtained. One hundred fourteen cases were further evaluated by clinical examination including electroretinography. Adjusting for incorrect diagnosis (eight of 114, 7%) and underascertainment (23 of 185, 12.5%), we estimated that prevalence of retinitis pigmentosa in Maine is 236 cases, 21 per 100,000 population or 1:4,756. Excluding Usher and Bardet-Biedl syndromes, the prevalence is 1:5,193. Estimated birth incidence of persons who will become affected with non-syndrome retinitis pigmentosa is 1:3,544. Incidence of newly diagnosed cases per year is about six per 1,000,000 population. Among kindreds, 16 of 85 (19%) were autosomal dominant, 55 of 85 (65%) autosomal recessive or isolated cases, seven of 85 (8%) X-linked recessive, and seven of 85 (8%) not classified by mode of transmission.