Survival factors: age at diagnosis, delay in diagnosis, frontotemporal dementia, gender, genetic factors and genetic modifications, type of onset and rate of progression, all of which are related to survival time. Age at diagnosis: In general, the younger the patient is at the time of diagnosis, the longer the duration of the disease. patients diagnosed under 45 years of age have a longer survival time; those diagnosed at an older age (65 years or older) have a relatively shorter one. Age may be a better predictor of prognosis than any other “immutable” factor. Evidence from several studies suggests that there is a strong correlation between age at diagnosis and length of survival. Delay in diagnosis: In general, the longer the time between onset and diagnosis, the better the chances of long-term survival; the opposite implies a shorter survival period. This may reflect the fact that the more aggressive the ALS case, the easier it is to diagnose early; at the same time, cases that develop more slowly require longer clinical observation (patients experience longer periods of time before they seek medical attention). Studies show that: frontotemporal dementia ALS has a shorter survival time than general ALS. Frontotemporal dementia symptoms involve cognitive decline, including personality changes and language impairment. It may be because people with frontotemporal dementia ALS have a tendency to refuse or ignore therapeutic measures (such as ventilatory support and feeding tube feeding). Gender: Survival time is shorter in women and relatively longer in men. The evidence for this is not entirely consistent, possibly because of the higher incidence of medullary ALS in women and the older age at which symptoms (onset) occur Genetic factors: Some familial types of ALS have been shown to be more aggressive than others. The duration of the disease depends on the genes involved and the mutations specified, and there may be differences even among members of the same family. Genetic/genetic modifications: There is speculation that altering genetic behavior but not DNA itself may have a positive or negative effect on survival time. These factors may be present in both familial and disseminated ALS cases. Rate of disease progression: A slower rate of decline after onset of disease implies a longer survival time and vice versa. A more severe symptomatology at diagnosis was associated with a shorter expected survival. The findings strongly support the relationship between the rate of disease progression and survival time. Type of onset: Limb onset (symptoms start in the arms or legs) has a better overall prognosis. Medullary onset (symptoms begin in speech, swallowing, and facial muscles) is usually more aggressive and has a relatively short survival time. Primary lateral sclerosis (PLS) and progressive (spinal) muscular atrophy (PMA) develop significantly more slowly. Evidence on these associations varies with different studies and may also vary due to the terminology used by physicians.