**4. Estimates of incidence**

MD is associated with several comorbid conditions such as arthritis (OR 1.8), psoriasis (OR 1.8), gastroesophageal reflux disease (OR 1.5), irritable bowel syndrome (OR 2.1) and migraine (OR 2.0). The development of cochlear and vestibular symptoms has a variable course and can

Depending on the series, the male/female ratio varies curiously. Some reports point out that Meniere's disease affects both sexes equally or there is a slight female preponderance, up to 1.3:1. Wladislavosky‐Waserman and colleagues reported a slight (though not statistically sig‐ nificant) preponderance of females. Following the three decades covered by the study, there was a progressive decline over time in numbers of women affected. In contrast, for men, there

Most studies suggest a slight female preponderance of up to 1.3 times that of men. MD seems to be much more common in white adults with higher body mass index categories, in their fourth and fifth decade. However, it can also be observed in children. A prevalence of 3% of MD was observed by Meyerhoff and colleagues in the paediatric population. Many studies have shown the existence of a positive family history for Meniere's disease with an index of relatives affected up to 20%.

The prevalence increases dramatically with age, peaking in the 60–69 years age group. It is very rare in people younger than 20 years [7]. This increase is shown in the graph in **Figure 2**. Already the incidence rate of Meniere's disease by gender according to age groups can be seen in **Figure 3**.

was a slight (but not significant) increase in rates for the same period [5].

**Figure 2.** Prevalence of Meniere's disease at different decade age in inpatients population.

take years in individual patients [12].

34 Up to Date on Meniere's Disease

Incidence is defined as the number of new cases occurring over a specified period of time, usually 1 year [9]. Incidence rate represents the number of new cases of a disease over a speci‐ fied period of time divided by the population at risk [5].

The incidence and prevalence in the general population are inferred from the exact values in the sample group [6].

Only prospective studies (subjects are identified prior to an outcome or disease; future events are recorded) have the power to measure incidence [5].

In 1954, Cawthorne and Hewlett attempted to estimate the incidence of MS by examining a reg‐ ister of clinical records for eight clinical practices in Great Britain serving a population of 27,365 people; they arrived at an annual incidence of 157 per 100,000. As pointed out by Wladislavosky‐ Waserman and colleagues, this number most likely represents a combination of incidence and prevalence, as some patients may have had onset of symptoms in preceding years.

In 1973, Stahle and colleagues examined records from a standard, nationally administered record system to determine the incidence of MS in a patient population from two cities in Sweden; they found an annual incidence of 46 per 100,000. Celestino and Ralli reviewed the records from 1973 to 1985 from a hospital and outpatient clinic serving a community of 1,03,797 people in Italy. The 1972 American Academy of Ophthalmology and Otolaryngology guidelines were applied for diagnosis of MS, and an incidence of 8.2 per 10,00,000 people per year was found [9].

A study in Cantabria evaluated epidemiological data. Incidence was determined by the num‐ ber of patients diagnosed Meniere's disease with per 100,000 inhabitants/year during the 11 years of the study and residents in the area having a health study excluding Meniere previ‐ ous diagnosis of disease. The incidence was 3/100,000 cases inhabitants/year prevalence of 75/100,000 (29 in men and 46 in women). The most common age of diagnosis was between 40 and 60 years [13].

In Japan, the average annual incidence was 5.0 per 100,000 population. Incidence and preva‐ lence predominated in females. With respect to age at disease, the incidence in elderly patients was increased when we corrected for age distribution in the overall population [10].
